Jeffrey Epstein, the well-connected sex criminal who died by suicide in federal custody, owned a 70-acre private island in the US Virgin Islands known as Little St. James.

The island's southwestern corner features an unusual blue-and-white-striped building that resembles a temple or place of worship.

The building has inspired countless conspiracy theories, but none has adequately explained what was inside the building or what Epstein did there.

Insider explored the most prominent and tantalizing theories about the building, including that it is a monument to an evil Canaanite god and that it is a crypt.

A piano tuner who lives in the Virgin Islands told Insider that he visited the building twice in 2012 and described its interior in detail.

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An entrance to an underground lair. An altar to an ancient deity. A monument to sexual predation. A defiant gesture, like a raised middle finger, toward the rest of the world.

These are just a handful of the various theories sprouting from the discovery of a strange blue-and-white structure on Little St. James, the private Caribbean island once owned and inhabited by the financier Jeffrey Epstein.

Epstein, who died last month, was said to have masterminded an international sex-trafficking operation, accumulated inexplicable sums of money, and organized his professional and personal lives around a private, inaccessible island — all while plying his way into the upper atmosphere of the global elite. The outlandish temple, with no clear history or purpose, provided the perfect detail: an otherwise minor plot element that promised to illuminate the whole story.

Still, no theory has convincingly explained why Epstein erected the building or what may have happened inside. The persistence of this mystery is especially remarkable given the intense public scrutiny of Epstein and his circle since his arrest in July. Someone, somewhere, must have a clue. Right?

In the two months since Insider highlighted the structure, I've received dozens of tips about its true purpose. Most had no basis in fact or reason. But along the way, I found the closest thing yet to the truth: an eyewitness account of the temple's interior, from someone who stepped inside long before it became a symbol of its owner's dark secrets.

Before we get there, however, let's run down the most popular — and probable — explanations.

Theory 1: It's a facility for child abuse or sacrifice

A favorite among online conspiracists, this theory combines the more fantastical elements of the Pizzagate and QAnon conspiracy theories, including cryptic allusions to pagan deities and underground chambers for abusing and murdering children. There are several variations of this theory, but many seem to stem from the presence of two birdlike statues perched on the building's roof.

One reader claimed that the statues depicted a deity of the ancient Canaanite religion, whose adherents practiced child sacrifice: "It's actually an 'owl,' and it's actually the same as the great 'owl' at Bohemian Grove ... The 'owl' is Moloch, a satanic entity that demands child sacrifice."

Another reader sent an annotated photo, below, that described the statues as harpies, the half-bird, half-human creatures of Greek and Roman mythology. The same photo compared the building's exterior to the striped flag of Greece and noted that "sex between adults and minors was common in ancient Greece."

An annotated image of the temple-like building. Anonymous

Both hypotheses are shaky.

Regarding the first: I was unable to find a historical example of Moloch being depicted as an owl, an idea that some authors have traced to "Dark Secrets Inside Bohemian Grove," a 2000 documentary filmed and produced by the radio fabulist Alex Jones. The title refers to a private campground owned by the exclusive Bohemian Club in San Francisco, whose members conduct elaborate ceremonies involving a gigantic concrete bird known as the Owl of Bohemia. Jones refers to the owl statue as "Moloch" throughout the film but never explains why.

Regarding the second: The mythological harpy possesses the body of a bird and the head of a human. The available photos of the statues, by contrast, show distinctly avian heads. There is a legible correspondence between the building's exterior and the modern Greek flag, and ancient Greek culture did promote sexual relationships between adolescent boys and adult men. But even if the building's motif alludes to the sexual culture of a society that ended more than 1,400 years ago, Greek pederasty was a male phenomenon. Epstein's victims were young women and girls.

(Confusing matters further is the disappearance or destruction of some of the building's architectural elements. During Hurricanes Irma and Maria, its golden dome blew off and was never replaced. The statues in front of and on top of the building, including Poseidon and the birdlike ones on the roof, appear to have vanished around the same time.)

In any case, these theories assert that Epstein built a designated structure to conceal his criminal activities and that he incorporated a series of obvious clues about those activities into the structure's design. This doesn't quite compute. If Epstein wanted to perpetrate crimes without interference, why would he do so in the most conspicuous building on his private island?

Verdict: Almost certainly not true. There is no clear evidence that Epstein constructed a special facility for abusing children or sacrificing them to Moloch or any other deity.

Theory 2: It's a gym

In July, ABC News spoke with an IT contractor named Steve Scully, who said he worked for Epstein and visited Little St. James more than 100 times. Scully claimed that his client used the building for exercise. From the report:

"A colorful building that some news reports have called the 'temple' was actually a gym when Epstein worked out when he was on the island, Scully said, noting in an interview with ABC News that the gym had a memorable feature — a massive framed photo of a topless woman."

This account, including the framed photo, is believable, except for one key detail.

Scully told the network that he worked for Epstein for six years, from 1999 to 2005. He later told The Virgin Islands Daily News that at the end of those six years he cut off contact with Epstein entirely. But based on historical satellite imagery from Google Maps, the blue-and-white building appeared on the island sometime between 2009 and 2013.

I was not able to make sense of this discrepancy. Maybe Scully never entered the building and only heard about its interior from someone else. Or maybe he visited the island and entered the building sometime after he stopped working for Epstein.

I wasn't able to reach Scully either. An email address found via public records no longer works, and a phone number associated with one of his companies was disconnected. Kaitlyn Folmer, a producer at ABC News, passed along my contact information to Scully, but I didn't hear back.

Verdict: Plausible, but the supporting testimony is inconsistent with the chronology of the building's construction.

Theory 3: It has something to do with ancient Egypt

One of the more remarkable features of the building is its exterior treatment: Wide, horizontal stripes, alternating between azure and white, that bend toward the tops of the windows and door. The design slightly resembles ablaq, a masonry technique used in mosques that involves layers of darker and lighter stone. Conspiracists have also pointed to a public bath in Syria, the family crest of France's House of Lusignan, and the set of Ellen DeGeneres' daytime talk show, "Ellen."

Some of these similarities are debatable, and some are absurd, but it is difficult to ignore the sense that the building resembles something.

"I wonder if it's a mausoleum with an Egyptian theme," one reader wrote. "The colors, design, and direction of the stripes are strikingly similar to the design in Tutankhamun's Nemes headdress."

A different reader added: "The statues look similar to those of Horus, the Egyptian god of the sky, wearing the Pschent, the double crown of Egypt. Horus was in control of the sun and the moon. Celebrated at winter solstice."

This is a tricky theory to parse. The building undeniably resembles the blue-and-gold fabric headdress worn by pharaohs in ancient Egypt. But it's not quite the same color scheme, and it would be difficult to prove, in the absence of Epstein's own admission, whether the resemblance is intentional.

As for the statue, or statues, of Horus: The available evidence is inconclusive. None of the available photos and videos that depict the golden statues is detailed enough to determine their identities, or if they even have one.

Verdict: Certainly possible, but still unproven.

Theory 4: It's a burial ground for his parents

Shortly after my original post about the building was published, a reader in St. John emailed: "I have it on good authority his parents are buried there. That would explain your question about the door lock," which curiously appears designed to prevent people inside from leaving.

"The other thing I remember," the reader later added, "was the Golden Owl on the roof pointed in a certain direction and that had [some kind of] meaning. I almost want to say it was the direction of where the parents lived." The reader explained that "this particular knowledge is from the boat captains that frequent the area."

The reader did not want to be named, but I was able to verify their longtime residence in the US Virgin Islands. And it would be strange for a reader to use their real name to lie about what a local boat captain told them about a particular building on Epstein's private island.

Still, the boat captains are mistaken. A death notice for Epstein's father, Seymour, appeared in The Palm Beach Post on December 16, 1991; a notice for his mother, Pauline (under her nickname, Paula), appeared on April 23, 2004. Both said that funeral services would be held at Menorah Chapels, later known as Menorah Gardens & Funeral Chapel, in West Palm Beach, Florida. A representative for the facility, now called the IJ Morris at Star of David Cemetery, confirmed that Seymour and Pauline Epstein are interred in a mausoleum there.

Verdict: Initially believable, but provably false. That said, it's possible Epstein designed the building as a future burial ground for his parents but never got around to having their remains shipped to the island.

Theory 5: It's a music room

This theory is based on three separate accounts.

The first was published by The Associated Press in July:

"Epstein built a stone mansion with cream-colored walls and a bright turquoise roof surrounded by several other structures including the maids' quarters and a massive, square-shaped white building on one end of the island. Workers told each other it was a music room fitted with a grand piano and acoustic walls. Its gold dome flew off during the deadly 2017 hurricane season."

The second account was published by NBC News in early August. According to the reporter Rich Schapiro, an unnamed architectural firm submitted blueprints for a domed, single-story building on Epstein's behalf to the Department of Public Works of the US Virgin Islands. The documents clearly show a building designed to show off a grand piano.

But as Schapiro acknowledged, the building substantially deviates from the blueprints, which describe an octagonal structure surrounded by a covered porch, with internal partitions for a bathroom, a closet, and a living room. The building, by contrast, is shaped like a rectangle and has no covered porch to speak of.

The third account came from a reader:

"Mr. Epstein did in fact have grand piano in that 'temple,' but the roof leaked because the AC units are on top, and the roof is flat. The piano was a '50s Baldwin Concert Grand ... so huge they had trouble getting it across the island and installed there ... It wouldn't fit the first time they tried (it was 1200 lbs). The leak was ruining the top of the piano, and the flooring. There were theater drapes in the room, and furniture. No stairs, no elevator. I know this because my friend ... has been in that room several times to tune the piano."

The reader supplied their friend's name, and I confirmed that a person by that name has worked as a professional piano tuner in South Carolina and Florida. But when I called that piano tuner, he told me: "I've never been to Jeffrey Epstein's private island. I don't know who gave you my name." He didn't recognize the name of the reader who referred me to him.

"It is true that I am a piano tuner with the Piano Technicians Guild," the piano tuner said. But he denied tuning pianos outside of Florida and South Carolina, or ever visiting the US Virgin Islands.

When I went back to the reader, they sent me a link to a YouTube video about Little St. James and claimed they had corresponded with the piano tuner via the comments underneath it. Indeed, someone had left several comments about entering the temple, using the piano tuner's name. "Was there a few times to tune his piano," one read, referring to Epstein. "Never saw him though."

Another comment read (minor typos have been corrected):

"Every time I was there it seemed some kind of repair was being done to structure. I know there were many issues with roof leaking and had to go there and move piano and cover it because they were putting up scaffolding to repair the roof that was leaking on piano. Not a lot in there except an absolutely huge 1960s Baldwin Model D concert grand piano and some furniture."

The piano tuner's denial is one reason to question this account. The piano-tuning industry is quite small, and while the piano tuner has a somewhat common name, I was unable to find a second piano tuner with the same name.

A second reason for doubt is yet another comment left by the same user:

"I didn't have any idea what was happening there at the time, it was early 2000s, so I really didn't pay attention to little details. I was just too excited to be on this beautiful island with a day to myself and this amazing piano. Those benches were there, sat there when I went out for a cigarette."

Remember, the building was erected between 2009 and 2013. But the YouTube user said he visited the building in the "early 2000s," long before it appeared in satellite imagery of Little St. James. For this reason alone, it is unlikely that this person ever set foot inside Epstein's temple.

Verdict: This is easily the most plausible and supported theory, but the available evidence is inconsistent.

So what was the temple for?

By mid-August, after speaking to the piano tuner who never tuned Epstein's piano, I was blocked and bewildered. I felt no closer to understanding the history of the building or the local lore around it. Wild rumors about child sacrifice and pagan symbolism were one thing; they came with the territory of the internet. But why would at least three people — the boat captain, the contractor, and the YouTube user — convey superficially plausible stories about the structure, sometimes in exacting detail, that didn't withstand basic scrutiny?

I had other doubts too. Soon after Epstein's arrest, a YouTube user going by the name Rusty Shackleford began posting a series of remarkable videos captured by an aerial drone flown repeatedly over and around Little St. James. It was Shackleford who captured the jaw-dropping scene of FBI agents executing a search warrant throughout the island:

But my doubts stemmed from two earlier, less-noticed videos that featured close-ups of the blue-and-white building.

As you can see in the clip below, the arched, medieval-looking "door" — the one facing the island's interior — is in fact painted to give the illusion of depth. Indeed, all the temple's external archways were illusions, painted on the building's featureless, flat surface as a trompe l'oeil:

In a second video, Shackleford's drone captured a portion of the building's interior, seen through one of the side windows. You'll notice what appears to be construction-grade scaffolding, two stacks of small mattresses, and an easel:

These developments were mystifying. Why would Epstein, who had access to seemingly unlimited amounts of capital, choose a mural of an elaborate door over the real thing? And what was the significance of the mattresses? The footage gives the impression of a makeshift storage locker, a discreet place to stash seasonal implements, but wouldn't Epstein have had other places to keep extra mattresses?

The assumption that Epstein acted according to a certain logic, and that that logic could be ascertained through research and reporting, seemed less and less certain. I began to question the whole point of the exercise. How much more time and energy was I willing to spend on a story with so many dead ends? Did it even matter what Epstein used the building for?

Every reporter has a personal theory of journalism — a mental model of the entire process that explains why they bother with it in the first place. One might think their job is about informing readers, or speaking truth to power, or helping people live better lives, or bringing about societal change, and so on.

My own theory is that journalism is about solving mysteries — identifying the unknown and finding a way to know it. That is a little embarrassing to admit, with its connotations of Scooby-Doo and alien abductions. But it's why I do it.

Yet here was a seemingly solvable mystery for which I could not find a solution. I found myself ashamed to discuss my progress with my editor and colleagues, as each additional clue turned out to be a false start.

The piano tuner's account provided the final clue

The episode with the piano tuner gave me one last idea.

Most professional piano tuners are listed in a directory maintained by the Piano Technicians Guild, a group in Kansas City, Kansas, that tests and certifies piano technicians in the United States. This was how I verified and contacted the first piano tuner, who said he never serviced Epstein's piano on Little St. James.

Using the directory, I looked up piano technicians in the Virgin Islands. After all, if Epstein did indeed keep a piano in the blue-and-white building, there was a decent chance he needed someone to occasionally tune it. (For pianos in regular use, the recommended frequency is twice a year.)

The directory returned a single entry: a piano tuner named Patrick Baron. So I sent him an email and left a voicemail asking if he had ever tuned a piano for Epstein. Then I tried to put the whole story out of my mind. If this didn't work, I planned to drop it altogether.

Three days later, my phone rang. It was Baron, and yes, he had tuned Epstein's piano.

A different piano tuner visited the building in 2012

Baron recounted his experience visiting Little St. James over several interviews with Insider. He never met Epstein, and he didn't recall how his staff originally contacted him — maybe through another client, or maybe through the online directory.

According to a calendar he kept at the time, Baron went to the island twice: in August 2012 and October 2012. On each occasion, Baron traveled to a dock in Red Hook, a town on the eastern end of St. Thomas, where he boarded a small boat that took him to Little St. James.

Baron didn't recall much about the boat's captain. But he did remember who greeted him on Little St. James. On the first excursion, he met a woman named Karen, who seemed to serve as the island's project manager. On the second excursion, he spoke with a woman named Monique who filled a similar role, though she never actually greeted him in person while he was on the island.

To support his account, Baron provided three phone numbers, one for Karen and two for Monique, that he used to call them in 2012. The first two numbers appear to have been disconnected, while the third, for Monique, went to a voicemail greeting for Southern Trust, a company that belonged to Epstein. When I called back a day later, I spoke with a woman who denied any knowledge of Southern Trust or anyone named Karen or Monique. Then she hung up.

After briefing Baron about the various projects she was managing, Karen handed him off to another employee, an older man who belonged to the island's maintenance staff. He drove Baron in a golf cart to the building where the piano was. The ride took about five minutes, along a path lined with palm trees.

Baron described the structure as a "relatively small building" near the island's coast, far away from the other structures on the island. It had a large glass door that faced "almost directly south." Atop the roof were statues that resembled "gargoyles." The color of the building — perhaps the most distinctive quality of the temple — was a "dull pewter." He didn't recall seeing any blue and white stripes on the exterior.

When Baron mentioned this, my heart sank. It suddenly occurred to me that he could have tuned a piano in one of the other buildings on Little St. James. But every other detail seemed to match the temple. When I emailed Baron several photographs of the building, taken from different angles and elevations, he called me a few minutes later: "That is definitely the building."

I asked if he was sure. "Absolutely. That's the right location. That's the right shape."

In other words, it seems as if Baron encountered the building before Epstein applied its distinctive striped exterior, including the realistic mural of a large wooden door.

Inside the temple, the piano tuner saw a Wurlitzer grand piano and a portrait of Epstein and the pope

After the golf-cart driver dropped him off, Baron entered the building. Here's what he remembers about the interior:

The floors appeared to be made of wood and were covered with a large Oriental rug.

The interior had two levels, with the first four to six feet at ground level and the rest on a slightly raised platform accessed by a single step.

To the right, against the eastern wall, was a nondescript gray couch or sofa.

Directly ahead was a desk, about 10 feet long, made of dark wood.

Behind the desk were several columns of floor-to-ceiling bookcases.

The bookcases went high enough to require a ladder. But there was no ladder.

The bookcases were filled with hardcover bestsellers. (Baron said he didn't notice "anything scholarly.")

To the left, against the western wall, was a small black grand piano. According to Baron's notes, it was manufactured by the Rudolph Wurlitzer Company, whose piano-manufacturing operations were acquired by Baldwin Piano Company in 1988.

Above the piano hung a portrait of Epstein and the pope. (Baron wasn't certain which specific pope, but when I showed him photos of the most recent three, he said his best guess was John Paul II.)

The interior consisted of only one large room; there weren't any doors or stairwells that may have led to other rooms.

On both visits, after Baron finished tuning the piano, the same golf-cart driver took him back to the island's dock, where the same boat captain returned him to St. Thomas.

Baron is almost certainly not the only person who stepped inside the blue-and-white building. Nor is he the only person who has publicly claimed to have done so. But he is the only visitor to offer a plausible and chronologically sound account of the building's interior.

I asked Baron what he thought the building was used for. "Even in the condition that I described it in ... it was sort of a temple," he said.

"When you say 'lair,' there is a connotation to that," he continued. "When you say 'study' or 'retreat,' there is a different connotation. I could have accepted it as a study or retreat, until I knew more about the man."

"I went in there knowing absolutely nothing about [Epstein], except that he was wealthy," he said. "And after doing the job and talking to some of my other clients on St. Thomas, and they filled me in on the scandal, my perception of that room changed from a study to a lair."

We now have a much clearer picture of the building's ostensible purpose. Based only on its furnishings, Epstein likely used the building to play piano, read books, work, and maybe relax. The music-room theory, it turns out, was the closest thing to the truth.

That might sound exceedingly mundane — the most boring answer to a tantalizing puzzle. But it also points to yet another mystery, one that may never be answered: What was Jeffrey Epstein doing on the rest of his island, and with whom?

Have a tip about Epstein or his island? Send an email to the author: ktrotter@insider.com.