
An impossible locked-room murder: Captain Mortuga lies dead beside an ancient cauldron aboard the world’s strangest submarine, crewed by sketchy suspects. A handcrafted point-and-click with sharp humour and tricky puzzles. Dive into the next mystery from the creators of Tangle Tower & Crow Country.
Modeled estimate, not a reported figure. How we estimate →
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About
In the pitch-black waters beyond a long-abandoned fishing town, the enigmatic captain of the world's strangest submarine has been murdered. Some say he was an immortal time-traveller. Others say he was a vampire, cursed to stay hidden beneath the waves forever...
Found alone in a locked room, with only an ancient stone cauldron to suggest how he might have died, it's up to Detective Grimoire and Sally to piece together what really happened. Was it a curse, released from the cauldron? One of the submarine's eccentric crew? Or does the bizarre truth run even deeper...
• Every clue is a fully realised 3D object waiting to be examined for hidden secrets
• Grimoire and Sally are back, and joined by a fully voiced cast of mysterious suspects
• A hauntingly beautiful original soundtrack performed by the Budapest Art Orchestra
• Explore every hand-painted inch of The Mortuga Submarine, where not all is as it seems...
*Voice audio is only in English
Stats
All-time low is the lowest price we've recorded for this game since we started tracking it.
Languages: English*, French, Italian, German, Spanish - Spain, Japanese, Korean, Portuguese - Brazil, Russian, Simplified Chinese, Spanish - Latin America, Traditional Chinese*languages with full audio support
Engagement
Hours played at review time, across 240 reviews with recorded playtime.
Reviews
Themes across 240 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
positive critical· bar length = how often the theme comes up
Reviews
Excellent writing so far. The vibes of this submarine are incredibly eerie. Every room you explore is super detailed, and clicking on any remotely interesting object results in some nice dialogue. The character designs are super endearing, and the music is haunting. The puzzles are great so far, whether they're done to open up a locked box or to connect some information using logic.
A game worth waiting for. I waited for years and it exceeded expectations. I had an amazing time and it's a great addition to the series. I don't know how I ended up having 22 hours on this game though, I think I spent a lot of time looking around, exploring, and talking to people... Goes to show how much fun I had lol. I hope one day, the devs will put up the original flash game. Every game has a lot of charm and whimsy, and it all began back with the original "Detective Grimoire", which I still go back to from time to time. I basically grew up with this series, which goes to show how good it is to continue following it nearly two decades later. They're all worth playing, you can see improvements and ideas evolve over time, and yet each one continues to be good and shown a lot of care. There's never a moment where you feel the creators were slacking or phoning it in.
Just as good as the first, and largely more refined. Maybe it was just familiarity with Tangle Tower, but I didn't feel like I stumbled nearly as often in either puzzles or investigation. An excellent sequel by every measure.
one of my most anticipated games :D it was amazing just like the others
Holy peak. Cannot recommend this game enough!! Please give it a try, I can promise you it won't let you down. (play tangle tower first tho ofc!)
So worth the wait! This game is INCREDIBLE! I love all of the Detective Grimoire games, and this one had me hooked right from the start. I love how unique the puzzles are and how I felt so accomplished after solving them. 10/10 amazing amazing game!
I don't usually leave review when finishing a game, but the puzzle, the investigation, the story, and the final reveal is just incredible. I am drawn to the game all the 10 hrs I played it.
Fantastic game. Expressive animations, compelling characters. rich art, rewarding story, top-tier voice acting, and one of the most creative soundtracks I've heard in recent memory. It's an absolutely fantastic game, indeed. Yes. Indeed. Indeed.
Un jeu de haute qualité comme ses 2 prédécesseurs, qui fait toujours la balance idéale entre humour, enquête, personnages attachants et mystère, et finit en belle note poétique, ouverte et mystérieuse comme à l'accoutumée. Certains passages concernant la discussion des indices et portraits avec les suspects peuvent être un poil longs mais le jeu en vaut la chandelle.
peak
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Trends
Steam followers (game-group members) tracked daily from when we started recording.
Momentum
Pace estimated from the game's recent review growth (our daily snapshots) at its own sales-per-review ratio — a momentum signal, not booked sales.
Audience
Audience
Games most often reviewed by the same players — an audience-affinity signal from our review sample, not full ownership data.
Estimated from the language of this game's reviews — a proxy for where players are, not official Steam demographics.
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