To celebrate the legendary manga One Piece surpassing 600 million copies in circulation worldwide, a special project titled "What is the One Piece?" was launched. As part of the event, creator Eiichiro Oda personally wrote down the answer to that very question—along with a certain truth about Luffy—sealed it in a high-pressure container, and had it sunk to the bottom of the ocean.
In a move that should surprise no one, less than 24 hours after the video dropped, fans on Reddit were already deep into detective mode, trying to pinpoint the exact location of this real-life treasure. They've even put together a detailed analysis of possible locations. Let's dive into their seriously impressive investigation.

So, where do fans think this underwater One Piece is hidden? Their theory is based entirely on clues from the official 600-million-copy commemorative video, using every bit of public information to narrow down a plausible location.
▼ The "What is the One Piece?" special project video
Clue #1: It's Probably Off the Coast of Japan
The leading theory is that the location is somewhere in Japanese waters.
The reasoning? Dumping something like this into the ocean is technically illegal. Given Oda's status, it's highly unlikely he'd do it without proper authorization, which means he probably secured permission from the Japan Coast Guard. The video's description also mentions the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), and the red and blue color scheme seen in the footage is believed to represent the Japan Coast Guard's official colors.
This suggests the drop point is within Japan's territorial waters, and the container likely has a tracking device for future retrieval.


Clue #2: No Land is Visible to the Southwest
A high-angle shot in the video, taken around 4 p.m., shows the sun setting in the southwest. Crucially, when the camera pans to the southwest, the horizon is completely empty—no land in sight.
The deduction: the camera/boat is facing southwest, meaning the coastline must be to the northeast. Based on the drone's altitude, the visible range would be roughly 30 to 50 kilometers. This means the drop point must have a vast, open expanse of sea to its southwest.


Clue #3: Depth of ~600 Meters, Fine Seabed Sediment
The video mentions the container was placed at a depth of about 600 meters. Footage of the seabed reveals fine, silty sediment. This is a key detail, as it indicates weak bottom currents and rules out areas with strong ocean currents, which are common in many marine regions.


The Fans' Best Guess: Suruga Bay
Putting all the clues together, the Redditor's top conclusion is "Suruga Bay," located in Shizuoka Prefecture.
The reasons are compelling: it's close to Tokyo (where Oda resides) and easily accessible. It's deep enough to meet the criteria, features weak bottom currents, and has no land visible when looking southwest. Most importantly, it's a frequent testing site for JAMSTEC, making it a near-perfect match for all the conditions.


The original poster added that the map fragments in the video might just be for artistic effect, though they could also contain real clues. They also acknowledged the possibility of creative editing but proceeded by assuming the footage was authentic to have a basis for their theory.
They capped it off with a joke: "If we actually find the One Piece, I vote we destroy it, just like in the movie One Piece: Stampede."

Of course, this fan theory isn't confirmed, but the fact that someone could piece together such a plausible location using available information so quickly after the video's release has drawn praise and attention from the community. For now, there's no way to know if they're right.
Still, it's a testament to the sheer size and dedication of the global One Piece fandom. You can't discount the analytical power of fans who are dying to know the series' greatest secret.
Other fans joked that Oda and the planners made one critical miscalculation: underestimating just how crazy the fans are. It was completely predictable that someone would try to find it.

Officials have stated that the contents of the note will be revealed after the story concludes. Perhaps only then will we find out if this incredible fan deduction was on the money. LOL.
via: Reddit