
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 →
Prices
The United States storefront in every case, so this compares stores and not countries.
Prices
Each in the currency that store quoted — not converted: the gap between two rows is the publisher's pricing, not an exchange rate.
Every market we collect.
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
Genres
Sums Steam only; PlayStation publishes no volume signal, so the true total is higher by an unknown amount.
| Store | Price | Audience | Score | Chart | Est. revenue |
|---|---|---|---|---|---|
SteamYou are here | $19.99 | 2.9Kreviews | 99% | — | $1M |
| $19.99 | 69ratings | 96% | — | not modelled |
Matched by title — a reused name can pair the wrong games. * is a critic aggregate. Prices and positions are each store's United States storefront; Epic charts worldwide. Audience and Score too, except Steam's, which is worldwide.
Engagement
Reviews
Themes across 1510 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
Reviews
I feel fortunate to have had steam recommend me this game - unbelievably charming and a joy to play from start to finish. the puzzles are fun and interesting, the story and characters are well-written, the voice acting and music are both great, and the art ties it all together. can't say enough good things about this game. looking forward to playing more from this studio.
An improvement on the already great Tangle Tower in every way. Lovely art style, loved the addition of 3d clues and the interactivity with everything. Really loved the way this one concluded especially compared to Tangle Tower. Just a really lovely time it's so good!
Media

Related
Related
Price dynamics, follower growth, revenue and sales trajectories with interactive tooltips
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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
Hours played at review time, across 1.5K reviews with recorded playtime.
positive critical· bar length = how often the theme comes up
A wonderful leap forward in narrative, design, and execution from Tangle Tower. It was exciting to see how the team has honed in their craft. Every conversation point is well written and the game is without any generic statements or wasted space. The chemistry between the two detectives is great and makes for a fun journey while solving the mystery. The Mystery this time is the biggest level up since Tangle Tower. That game had a great mystery box, that was unfortunately lackluster once opened. The premise to the murder this time is a wonderful closed mystery room that actually delivers and a superbly crafted and well delivered resolution that exceeds expectations as a murder-mystery narrative.
yes
Amazing mystery story and puzzle game! I have played all four Detective Grimoire games and this is the best one yet. Great atmosphere, great characters, great length, and challenging mysteries/puzzles.
Excellent jeu comme d'habitude avec la sage Détective Grimoire. Humour vif et animation incroyable, mystère juste comme il faut en terme de difficulté. Très bon jeu !
Cara, o que dizer sobre a SFB? Conheci eles com Tangle Tower, e descobri depois que eles haviam feito o meu jogo de infância preferido, e para minha felicidade eles haviam anunciado outro jogo do Grimoire, o Mermaid Mask. Então, o que dizer sobre o Mermaid Mask? Um jogo 10000/10, os caras conseguiram pegar o que era incrivel em Tangle, e melhorar mil vezes. A história é muito cativante do inicio ao fim, eu queria terminar logo e mal conseguia parar de jogar; os personagens incriveis. E você nunca desconfia do culpado, e nem do que realmente vai acontecer. Da para perceber o carinho que eles poe nesses jogos, e principalmente quando você le as anotações da galeria de arte, e digo, parabéns a todos que trabalharam no jogo, e nas artes. Gostaria que muitas pessoas conhecessem esse jogo pois VALEU CADA CENTAVO.
Banger
An amazing addition to the series!
故事实在是令人唏嘘,通关后久久不能释怀。 海面之下压抑着人鱼哀恸的吼声,海面之下悬坠着漂流之船虚无的终点...
Selling now
See how fast this game is selling right now — estimated copies and revenue per day from recent review growth.
Active players
Estimated daily and monthly active players (DAU/MAU) modeled from peak concurrency.
Players by region
Where this game's players are, estimated from review languages.
Players also reviewed
The games this title's players most often review too — audience affinity.
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| $3.7K | 15 | 67% | $14.99 |
Related
| Game | Estimated lifetime revenue | Reviews | Review score | Price |
|---|---|---|---|---|
| $1M | 993 | 87% | $34.99 | |
| $1M | 2K | 58% | $19.99 | |
| $1M | 1.3K | 40% | $19.99 | |
| $1M | 1.5K | 73% | $19.99 | |
| $1M | 3.1K | 92% | $13.99 | |
| $1M | 1.5K | 81% | $19.99 |