
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 1498 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
Reviews
Absolutely wonderful game. Just a joy, start to finish.
Great game. Not too but it's really dense unlike a lot of pointing to the adventures, it never feels particularly frustrating. Obviously, one of the big draws is the visuals narrative and just all the artistry that went into it, which is obviously top-notch. Would definitely recommend this game to anyone in the pointing click adventure. The games never particularly challenging but I don't think it needs to be to be good. This is my first game in the series and I intend to play more
Media

Related
Related
Price dynamics, follower growth, revenue and sales trajectories with interactive tooltips
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Related
| Game | Estimated lifetime revenue | Reviews | Review score | Price |
|---|---|---|---|---|
| $1M | 992 | 87% | $34.99 | |
| $1M | 493 | 83% | $49.99 | |
| $1M | 1.3K | 40% | $19.99 | |
| $1M | 1.5K | 73% | $19.99 | |
| $1M | 3.1K | 92% | $13.99 | |
| $1M | 1.5K | 81% | $19.99 |
Related
| Game | Estimated lifetime revenue | Reviews | Review score | Price |
|---|---|---|---|---|
| $1.8M | 6.8K | 95% | $19.99 | |
| $607.9K | 1.8K | 92% | $14.44 | |
| $83K | 291 | 87% | $15.99 | |
| $37.1K | 256 | 89% | $9.99 | |
| $13.2K | 109 | 95% | $8.99 | |
| $3.7K | 15 | 67% | $14.99 |
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
Großartige Spielereihe Die Dectective Grimoire Reihe macht alles richtig, was ich sonst nicht an Point & Click Adventure mag. Ich liebe vor allem die Charaktere und die Geschichte, und da macht "The Mermaid Mask" keine Ausnahme. Es ist das bisher längste Spiel der Reihe und ich hab auch schon wie bei den anderen Titeln jede Sekunde genossen. Ich hatte das Gefühl, dass die Rätsel bisher die schwersten der Reihe waren, aber sie waren immer schlüssig. Auch wenn es eine Spielreihe ist, steht jeder Teil für sich und es ist nicht notwendig, die Vorgänger zu spielen. Es ist auch schon eine Weile her, dass ich die vergangenen Teile gespielt habe. Deshalb habe ich manche Verbindungen nicht erkannt, es wird also mal wieder Zeit.
Overall an incredibly tight package, which is to be expected of SFB games as I felt that Detective Grimoire and Tangle Tower were two excellently constructed games that I thoroughly enjoyed already. First off, the aesthetic of the game is just gorgeous, with some energetic animations that make it great to look at from start to finish. Featuring Layton-esque puzzle solving and Ace Attorney-esque mystery solving, I feel like this is my visual novel wishlist in how it manages to combine some genuinely engaging brain teasers with a compelling mystery that I admit I had only partially solved by the end (which, in my view, is how a detective novel should always be - you should have been able to guess who the culprit is based on the vibes and a few clues in the story but not have pieced it together into a cohesive narrative until it's explained at the 'cliche monologue' as one of the characters puts it. I think it managed to walk a fine line between endearing and quirky with its character work, as I felt the full cast was charming in their own way without veering into too annoying to bring down the overall vibe of the game. Thoroughly enjoyed and highly recommend.
SFB Games, could you make your next release smaller so we don't need to wait 5+ year for the next DG?
Great game
This was a really fun yet challenging mystery! All of the characters were charming in personality, history, and especially in their design. I do appreciate the optional hints as well, as sometimes that small point in the right direction is what I need from a game like this.
Great writing. I never felt stuck but also didn't just breeze through the puzzle. I REALLY loved this!
NB B NG 캐릭터들의 특징들이 다 좋았어요
The presentation for the mystery and untangling the suspicions is so much more ambitious and I think it largely pays off. Stellar voice cast once again. Some minor qualms about the mystery setup but those barely matter. Introducing 3D for some puzzles helps with variety and the space within which you have to think. All in all, a very fun game with a great cast of characters to spend time with and pick apart the lies to get at the truth.
Selling now
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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.