By David Wolman
 Photographs and videos by Jake Michaels
 Nov. 27, 2022
 When Abigail Danian walked into her kitchen and saw the empty packaging of a burner cellphone on the counter, she knew Isaac had gone. It was Sept. 7, 2020, and she had been out of town for Labor Day. All weekend, her 20-year-old son, Isaac, had been calling her from the family home in Grand Rapids, Mich. He needed money for a “great opportunity” in Hawaii, but that was all he would say.
 The next morning, Ms. Danian’s husband, John, headed to the local airport. He drove the rows of the parking lot, pressing the panic button on a spare key until he heard the horn blare from Isaac’s silver Volkswagen Passat.
 A few days later, Isaac called his mother. He wanted her to know he was safe and asked to talk with his young siblings, both of whom adored their big brother. He was in Hawaii, he said, but he still wouldn’t elaborate. Ms. Danian’s mind raced. Whom was he with? Had he joined a cult? How could she talk him into coming home?
 A few weeks passed before Isaac called back. This time he informed his parents that he would be off the grid for 30 days but would be back in touch when he could.
 Ms. Danian never heard from him again.
 Four weeks before Isaac left his home in Michigan, Shukree Abdul-Rashed called his wife in Rochester, N.Y. Mr. Abdul-Rashed, 26, tried to explain to her why he had quit his postdoctoral chemistry program and suddenly abandoned the life they had been building together. The military would soon be going door to door, he said. They were coming for him, for her, for everyone. She kept her composure during the call, but inside she was panicking.
 It was the end of August 2020, and by that point his wife, who asked not to be identified out of fear of online harassment, had become familiar with her husband’s delusions and eruptions of hopelessness — disturbing changes that had coincided with the pandemic lockdown. But at least he had been at home.
 “OK. Well,” she said, pausing. “Do your parents know? Are you safe?”
 He said he was, but wouldn’t say more. Not long after, he connected with his wife on a video chat. Again she asked where he was. He would only say that he was with a “like-minded brother.”
 The undertow of unreason had pulled Mr. Danian and Mr. Abdul-Rashed away from their loved ones, though it was not yet clear just how far away it would carry them.
 To his wife, Mr. Abdul-Rashed’s transformation during that first spring and summer of Covid had been devastating. Mr. Abdul-Rashed was practicing muslim and a Ph.D. candidate in organic chemistry at the University of Rochester, researching novel techniques for building complex molecules. By the spring of 2019, he was already winning prizes, about to publish in a peer-reviewed journal and working to promote diversity in STEM. “He was charming and funny,” his wife said, “and super smart, obviously.”
 Shukree Abdul-Rashed in 2019. To his wife, Mr. Abdul-Rashed’s transformation during that first spring and summer of Covid had been devastating. Abdul-Rashed Family
 But as the lockdowns of 2020 wore on, Mr. Abdul-Rashed’s wife began to notice that her husband was also spending a lot of time online, and that those sessions were agitating him. When she asked what he was watching, he would say something like, “Just YouTubers or whatever.” Glancing over his shoulder now and then, she saw “plandemic” videos about Covid-19 and bizarre ultraconservative content about Satan’s grip on the government.
 Nevertheless, when she confronted him, she was careful not to make him feel cornered or belittled. “If you choose to marry someone, they deserve your patience and kindness,” she told me. Through the summer, she endured as best she could. Mr. Abdul-Rashed phased in and out of his troubling state, continuing his organic chemistry research and being an attentive spouse one day, sinking further into paranoia and despondence the next.
 In mid-August, he met with his adviser, Dr. Alison Frontier, a chemistry professor. Seated beneath a giant oak tree on campus, Mr. Abdul-Rashed got straight to it. “I want to resign from the program,” he told Dr. Frontier. He was done with academia and needed to focus on other things, namely spreading the word about Satan’s plan for controlling humanity, bogus vaccines and the imminent apocalypse. Dr. Frontier was at a loss, and she remembered thinking: “This is a scientist who understands how vaccines work. How does this happen? How is science suddenly thrown out the window in favor of the will of evil men to control the world?”
 For the Danians in Michigan, their son’s troubled state of mind wasn’t a complete surprise. Years earlier, he had been treated for depression, but his mental health had since improved, and he had recently started working at a restaurant. Then in early 2020, he had “developed paranoid thoughts” — made worse, Ms. Danian said, by the pandemic, widespread social unrest and the presidential election. He started posting videos in which he talked about a totalitarian government, Armageddon and finding Christ.
 He proposed that the family study scripture with him. He was desperate for others to see what he saw. In one wandering, almost breathless, message, he wrote, “As the Bible said we fall for lack of knowledge.”
 Isaac Danian celebrated his 20th birthday just a month before he abruptly left for Hawaii. Danian Family
 By that point, the Danians feared that Isaac might be suffering from schizophrenia or some other mental illness. But before they could persuade him to get help, he was on a plane to Hawaii.
 Back in Rochester, Mr. Abdul-Rashed’s wife kept rethinking the conversation in which her husband had said he was with a “like-minded brother.”
 “That triggered me to go and look and see who he was interacting with,” she said. She went to her laptop and began poring over her husband’s social media posts. She also remembered two T-shirts Mr. Abdul-Rashed had bought a few weeks before leaving. They depicted a Black Jesus with glowing white eyes, and the slogan “Vaccines are the Mark of the Beast 666.” In smaller print, there was the URL of a YouTube channel.
 She typed the address into a new tab and was led to a collection of posts by a man with dirty-blond dreadlocks and a tattoo across his forehead that spelled out, in archaic Hebrew, “Yahweh.” The caption accompanying the most recent video read, “Last opportunity to join me and friends in our exodus.” He was looking for any men — because women, in his view, were a temptation to sin — of sound mind and studious nature who wanted to “bug out” of this obviously doomed society and start rebuilding civilization as God intended it.
 On their next video call, Mr. Abdul-Rashed’s wife asked her husband directly: Are you with this man with the tattoo? He said yes, but again refused to say where he was. While he spoke, his wife noticed tropical vegetation in the background and thought: “definitely not Rochester.” A few weeks later, she found an order receipt for the T-shirts, which included a return address in Hawaii.
 “Oh my God — this is it!” she shouted.
 The tattooed man’s name was Matthew Mellow, though he had been born Matthew Logue. On his YouTube channel, Facebook and other social media, he went by the alias Mortekai Eleazar.
 Mr. Mellow grew up in Orange County, Calif., where he became an avid body boarder. When he was 20, he moved to Hawaii, where he made ends meet refurbishing scooters. In the early 2010s, Mr. Mellow set out for still more distant shores, traveling to many famous surf breaks in the South Pacific. But by 2020, he was back on Oahu, living with his mother.
 Mr. Abdul-Rashed and Mr. Danian had found Mr. Mellow and watched his YouTube channel, where he preaches not so much an atypical theology but a sprawling word cloud. He jumps from lambasting Christianity to evangelizing about the proper way to walk with Jesus. He eschews romantic relationships (for now) and sermonizes on masturbation, Satan and the evils of Covid-19 testing. And always the refrain, “I’ve done the research.”
 On YouTube, Matthew Mellow asked people to join him in the South Pacific to rebuild the kingdom of Christ.
 The three men seemed to share a worldview that Satan had unleashed a plan to destroy society, and the pandemic was proof. As their conviction grew into fervor, they decided that the situation called for — that God called for — dramatic action. Mr. Abdul-Rashed and Mr. Danian traveled to Hawaii to connect with Mr. Mellow, their spiritual guide and Pacific expedition leader. The exodus was on. All they needed was a ride.
 Mr. Mellow posted an ad on Facebook and Craigslist offering $10,000 for passage to the South Pacific. “Mom (Petra) and I are looking for a captain/charter to sail us to Rarotonga Cook Islands,” the post read. “We are ready to go at any time in the coming days/weeks.”
 Michael Schmidt and his friend Jeffrey McKinley took him up on the offer. Neither man’s sailboat was big enough for the whole group, so they would have to take both.
 Mr. Schmidt was a 58-year-old itinerant mariner who sold used phone systems and sometimes worked as a charter fishing boat captain and shark-fishing expert.
 Michael Schmidt, left, and Jeff McKinley in Honolulu in 2020. With their small sailboats, the two men agreed to take a group of passengers they had found on Craigslist to the South Pacific. Jeff McKinley
 Like many Americans, Mr. Schmidt was skeptical of Covid coverage in “the mainstream media.” He believed the government was using the pandemic as a pretense to exert control. He followed various conspiracy-minded social media accounts and had begun to fear fictions like nanobots in the bloodstream and Covid concentration camps.
 At first, Mr. Schmidt was wary of the charter. “I thought maybe these guys were wanted,” he told me. But earning a few grand on a South Pacific voyage sounded better than idling his way through months more of what he called “the shamdemic.”
 The morning of Oct. 6, 2020, with Mr. Danian and Mr. Abdul-Rashed aboard, Mr. Schmidt leaned over the bow of his boat, Zulu Time, pulled anchor, and shoved off for the nearly 3,000-mile voyage to Rarotonga in the Cook Islands. Mr. McKinley’s boat, A-Loona, departed a few days later carrying Mr. Mellow and his mother, Petra Walter-Logue.
 Aboard Zulu Time, Mr. Schmidt was at ease. While the rest of the world policed six-foot spacing and nervously wiped down groceries, he was traveling the open ocean, answerable to no one.
 His passengers seemed equally content. Neither of them knew anything about sailing, but still they buzzed with excitement about the journey ahead. Mr. Danian was clumsy but amiable, Mr. Schmidt remembered. “He’s out in the real world, not his mom’s basement in Michigan,” Mr. Schmidt told me. “It was, like, putting the zap on him. His eyes were as big as saucers about the whole thing. He was going on this big adventure.”
 Mr. Abdul-Rashed was more serious, spending hours reading the Bible or in intense conversation with Mr. Danian about religion, the pandemic and the “New World Order.” To Schmidt, the fact that Mr. Abdul-Rashed, a doctoral candidate, rejected the prospect of vaccines and spoke of a secret government agenda reinforced his own convictions.
 The sailing was great, at the start — “Yahoo!” Mr. Schmidt texted to a friend early on. They put out fishing lines to supplement their store of rice and canned food, and Mr. Schmidt recorded a short video of Mr. Danian and Mr. Abdul-Rashed after they had hauled in a wahoo and a small yellowfin tuna.
 Mr. Danian and Mr. Abdul-Rashed aboard the boat Zulu Time. Mike Schmidt
 But soon enough, the weather bore down. “I have been in many squalls,” Mr. Schmidt texted a friend back in Hawaii after five days at sea, “but this had that scary scream to it just like in the movies.” Sideways rain hammered the men, and waves washed over the Zulu Timeas ocean and sky became a wall of white.
 On Oct. 23, two weeks and about 2,000 miles from Hawaii, the captains learned that because of the worsening pandemic, Cook Islands ports were closed. They continued on the same course for a few days, hoping officials might grant them some sort of exception to the no-entry rule. No allowance came, and around Oct. 28, Mr. McKinley set an eastward course for Bora Bora in French Polynesia, an additional 300 miles away. Mr. Schmidt reluctantly followed.
 But redirecting meant sailing almost directly into the prevailing wind. At one point, the waves were so big that, Mr. Schmidt said, he broke his nose while being tossed around the boat. He was furious. Just before midnight on Halloween, he sent Mr. McKinley a message about the grueling conditions: “This 500 miles is going to turn into 800 miles with all the tacking. I don’t think we have enough water for another week of this. Fiji would have been better.”
 The morning of Nov. 5, after six days of zigzagging toward Bora Bora with only incremental progress, Mr. Schmidt turned his boat to begin sailing west, toward Pago Pago in American Samoa.
From Hawaii to French Polynesia
By The New York Times
 By this point, Mr. Schmidt knew full well that his passengers were scared of being tested for Covid. They believed that the test — not the vaccine, but merely the test — would sever their connection to God and unite them with Satan.
 Mr. Schmidt was in sync with the young seekers when it came to fear of Big Brother and vaccines, but dreading port officials brandishing nasal swabs struck even Mr. Schmidt as a little unhinged. “I tried to talk sense into them until I was blue in the face,” he later told me.
 As the boat neared American Samoa’s main island, Tutuila, Mr. Abdul-Rashed and Mr. Danian begged Mr. Schmidt to drop them just offshore; they would make do from there. They had even packed small bags with supplies — “lighters, bandages, stuff like that,” Mr. Schmidt recalled — and back in Hawaii they had been practicing how to paddle to shore from more than a mile out.
 The trio sailed to within a mile of shore, but no closer. Zulu Time’s motor had stopped working just days into the trip, and Mr. Schmidt told me he was daunted by the prospect of sailing into, and then out of, a challenging and unfamiliar harbor. At the last moment, he changed his mind and turned back out to the open ocean.
 In April 2021, seven months after their last call from Isaac and still hoping that he was alive and only choosing to be out of touch, the Danians filed a missing-person report with the Grand Rapids police.
 A few weeks later, Ms. Danian took her private torment public, with a Facebook post that began: “I am only putting this out here in hopes that people can share. Isaac has been missing since Oct. 4, 2020.”
 Thoughts and prayers poured in, as did tips. One reader suggested she contact people who run fishing charters or work as deckhands out of Kona Harbor. A person who used to tend bar in the area said that Isaac looked “super familiar” and that she might have seen him in February. (She hadn’t.) Another person suggested checking Cinderland, a commune-like “eco-village” on the south part of the island of Hawaii. Ms. Danian followed up on every suggestion, but none panned out.
 On May 18, she was grilling on her back porch when she and John received a bizarre phone call. An interpreter on the line said she was with an investigator from a French territory in the South Pacific, Wallis and Futuna. They had found Ms. Danian’s name through Facebook. The woman informed the Danians that the local authorities were looking into a disappearance — something to do with a sailboat that had arrived at the island back in November.
 When Ms. Danian heard the person say something about “no proof of life but no body either,” she collapsed on the porch, sobbing. The possibility that Isaac had drowned was crushing. She had been trying for months to keep her composure so that life felt “as normal as possible” for her two younger children, but this news made her feel like a zombie.
 Mr. Danian’s family made a flyer that was posted digitally and distributed by hand in the area where he was last seen in Hawaii. Danian Family
 A week later, a Grand Rapids detective received a call from Mr. Abdul-Rashed’s wife, who explained that her in-laws had also been contacted by the authorities on Wallis. She then told him about the T-shirts, the receipt and the tattooed guy’s YouTube posts.
 Ms. Danian immediately reached out to Mr. Abdul-Rashed’s wife. The two women were now connected in frustration and anguish.
 The critical moment that neither of them knew about, though, had happened on Nov. 28, 2020.
 After the aborted stop at Pago Pago, the trio aboard Zulu Time desperately needed a place to make port. The world was essentially closed, and the boatwould soon run out of food and water. On Nov. 18, a friend back in Hawaii suggested via text that Mr. Schmidt continue about 500 miles farther west, with the wind, to Wallis and Futuna.
 Ten days later, Mr. Schmidt was sailing Zulu Time into the narrow channel off the south end of the main island, Wallis. The current was strong, and the boat was moving at a swift clip, flanked by shallow, jagged reefs.
 Mr. Abdul-Rashed was “very nervous and worried,” Mr. Schmidt later told the police. And Mr. Danian, he said, “was like a soldier being dropped off at war.”
 Mr. Schmidt added: “He wasn’t listening. I asked him to stand by. He started tying the ropes the wrong way. In hindsight, I think they weren’t thinking about what was going on on the boat; they were thinking about something else.”
 As Mr. Schmidt told it, the two passengers had gone below deck while he was navigating the tight channel. Suddenly, before Mr. Schmidt realized what was happening, Mr. Abdul-Rashed emerged. Agitated but resolute, he leaped from the port side into the water. A moment later, Mr. Danian came up, muttering, “Sorry about this,” and jumped too.
 Mr. Schmidt was dumbstruck, and then irate. He yelled after them: What are you doing? But he had to turn his attention forward and couldn’t keep his eyes on them for long. Needing to consult his charts, he went below deck for a minute, maybe two. When he stepped back into the sunshine, he said, all he could see behind the boat was the blue expanse stretching to the horizon.
 For many months after Isaac had left, Ms. Danian had been operating under the assumption that her son was still in Hawaii. The call from Wallis changed that, but it would be a further five months before she was given the investigation report for review. Even with that in hand, she remained hopeful that her son was still alive. She felt Mr. Schmidt’s account in particular was suspicious.
 Mr. Danian’s wallet and its contents, in a photograph taken by the police on the island of Wallis and included in the report on his and Mr. Abdul-Rashed’s disappearance.
 The police were also skeptical of his story and interrogated him several times. According to the report, they searched his boat exhaustively and confiscated his 9-millimeter pistol and later his laptop.
 They wondered, for instance, why he had pulled up Covid conspiracy videos on YouTube as soon as he had internet access on Wallis. He “never stops watching videos about the end of the world, conspiracy, Covid, unexplained phenomena,” the report reads.
 Also, relevant data from Mr. Schmidt’s satellite navigation system had recently been erased. He told the police that he didn’t remember deleting anything and that he no longer had the login information.
 Had Mr. Schmidt, the police asked, perhaps dropped the men off on a small barrier island so they could swim to the main island later, undetected?
 No, Mr. Schmidt insisted. “If I had been in on the act, I would have left them on an island in American Samoa,” he said.
 Then why hadn’t he taken the most basic step in a man-overboard situation, tossing something like a life jacket, a body board or a seat cushion into the water after them? “I told myself that I couldn’t help them because they wouldn’t want help,” Mr. Schmidt explained to the police. “From what I had heard, they believe that the Covid test will give them the mark of the beast and thus they will go to hell.”
 After a four-month inquiry that included interviews, reviews of weather data, underwater searches, DNA analyses and digital forensics, the local authorities concluded that the most likely explanation was that Mr. Danian and Mr. Abdul-Rashed had indeed jumped from the boat and had been swept out to sea.
 When pressed in an interview about who was responsible for what happened, Mr. Schmidt grew exasperated: The two guys were crazy, they’d jumped, and it wasn’t his fault. Mr. Mellow was the person to see, he said.
 In Ms. Danian’s retelling of her last conversation with Isaac, she had pleaded with him to tell her where he was going. “I remember him saying it’s better if I didn’t know,” she said. “He was obviously being coached on this, and I could tell in his voice that he was disappointed that he couldn’t share with me.”
 “Matthew Mellow is the reason Isaac has disappeared,” she said.
 There is a take on this story in which two adults made their decision and faced the consequences. Maybe they didn’t intend to drown, but if Mr. Schmidt is to be believed, they certainly intended to jump. End of discussion.
 But what part did Mr. Schmidt play? He was the captain, after all. How did he not throw even a seat cushion after them?
 And the journey itself — that was Mr. Mellow’s idea. Is he responsible? What about the wider question of responsibility?
 Most of us take part in a world that incentivizes sharing of misinformation and disinformation. On social media especially, the boundary between merely strange beliefs and true detachment from reality can blur. After so many hours of clicking and watching, the susceptible among us lose the ability to discern truth from fiction. When such alternate realities take hold, we dismiss the believers as delusional.
 At least some sense of an answer might lie with Mr. Mellow, who by the spring of 2022 had settled on the tiny French Polynesian island of Huahine. He agreed to meet at the Huahine Nautique, an open-air dockside restaurant in the island’s commercial center.
 When Mr. Mellow arrived, the full beard and dreadlocks from the YouTube videos were gone. He was wearing a white polo shirt and carrying a gray-and-pink flowered backpack full of books. Around his head, he wore a bright bandanna that covered his distinctive Yahweh tattoo.
 Mr. Mellow outside the Huahine Yacht Club in December 2021. He spends his time on the island surfing and evangelizing to islanders.
 He explained that his spiritual awakening had come in 2014, as he watched a television show called “Prison Break.” In the series, a vast government conspiracy unfurls over many seasons, and when the show ended, a stunned Mr. Mellow turned to the internet. “I went on Google, and I typed in, ‘Does a small group of people control the whole world?’”
 He spoke with a strange detachment, a cadence more TikTok than televangelism. There is so much garbage online, Mr. Mellow said, that the truth ends up buried in remote corners of the internet, labeled “conspiracy theory” or simply censored. “I’m not the one who is wrong,” he said. “Everyone else is. Have you seen ‘The Matrix’?”
 In the year and a half since he and his mother had arrived in French Polynesia, Mr. Mellow had kept busy recording videos of himself addressing matters of scripture and Covid and posting them to YouTube, Facebook, BitChute, Discord. In real life, he continues his “ministry,” traveling to nearby islands preaching about the Illuminati, numerology, gene editing and Covid testing. “It’s not really a swab test,” Mr. Mellow said. “It’s nanocoils that look like cotton” and deliver “nanotechnology into people’s body, mostly their brain.”
 Nearly everyone on Huahine seemed to know of Mr. Mellow; it’s a small place, after all. He rides his bicycle around, passing out tracts. A man working at my hotel said Mr. Mellow had come to his house when he wasn’t home and had told the man’s children to refuse the vaccine and had then slid rolled-up copies of his flier through a hole in the lattice fencing.
 Mr. Mellow said with pride that he had to date distributed 21,800 copies of this document. “I’ve been able to help people here,” he said, clearly relishing the missionary quality of his new life in French Polynesia, an analog node in the digital global conspiracy machine.
 Mr. Mellow created a flier in French for locals to read, which he passes out on Huahine. It details his theories about the Covid-19 vaccine and how it relates to the Book of Revelation.
 Despite the short time together before setting off on different vessels — about six weeks with Mr. Abdul-Rashed and just a few weeks with Mr. Danian — Mr. Mellow said he had felt a deep connection. “They loved me; I loved them,” he told me. “They turned out to be the best friends I ever had.”
 And their refusal to be tested for Covid? “Absolute heroes,” he said. “I believe that my brothers died in God’s graces.”
 At one point in the interview, perhaps realizing for a moment how he sounded, Mr. Mellow said, “There’s lots of people who believe in what I believe.”
 For Abigail Danian, back home in Michigan, it has been nearly a year and a half since she first heard from the authorities on Wallis. She had a hard time even saying Mr. Mellow’s name, and she remained deeply skeptical of both Mr. Mellow’s and Mr. Schmidt’s accounts. She continues looking for clues within the hundreds of pages of the investigation report and prodding the U.S. State Department to investigate her son’s death. (The State Department and the F.B.I. both declined to comment on the case.) She has also set up a website, findisaac.org, where people can leave tips. Two years after Isaac reportedly jumped from the boat, she still believes her son is alive somewhere.
 When asked if he was at all responsible for what had happened to Mr. Danian and Mr. Abdul-Rashed, Mr. Mellow looked genuinely confused. Mr. Schmidt was the captain of their boat, and they disappeared 1,500 miles from where Mr. Mellow had ended up. How could he possibly be responsible?
 But what of his role as the organizer, as the Moses leading this exodus? Mr. Mellow grew agitated. “They studied these things on their own — maybe they watched my videos,” he said, but the two men were products of their own research. “They contacted me.”
 When making to leave, Mr. Mellow seemed to consider how he might come off in this portrayal. He repeatedly asserted that he was not “crazy.” “If you write that I’m crazy, I’ll lose a lot of faith in humanity,” he said.
 Mr. Abdul-Rashed’s wife also worried about how this whole story might sound, how the world would think of her husband. She chose to share, though, because she had watched her husband slip away and had learned how quickly that could happen to someone.
 “I just wanted to let you know Shukree wasn’t crazy,” she said. “I want you to know he was a good, charming, loving person. I want that to be known, so he knows he was loved.” She paused. “In case he ever reads this.”