
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 1483 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
Reviews
I can't wait to re-play it and note down all the clues within clues the developers left. Incredibly polished game. Best in the series. If you're looking for a visual novel detective story, this is up there with Phoenix Wright and Professor Layton.
Another solid - no, better than solid, *excellent* addition to the Detective Grimoire series! I'm not sure what to say that hasn't already been said by the other reviews, but I do want to praise just how polished and high quality this game is. The voice acting, character designs, dialogue, music, animations, all of it is tight as hell. I really enjoyed solving each puzzle too, I can see the amount of labor and attention the devs put in to make each one unique and interesting but not too frustrating. That's a real hard needle to thread and they get props for that (even if I did have to look up the answer to one or two). Can't wait to see what direction the series and/or dev team goes in the future!
Media

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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
An absolute delight in my eyes! Beautiful art style, music, characters, and gameplay! And the voice acting is fantastic! I bought the game on launch, and it was worth every cent. I was thoroughly entertained from start to finish. You can really tell how much effort, care, and love went into making this game, and I genuinely hope the developers are proud of what they achieved. ❤️ I hope lots of people give this game a chance. It's not overly difficult and should appeal to a broad audience. I'll definitely be recommending it to anyone I know who enjoys detective games. [spoiler]Thank you, SFB Games, for giving us Muscle Mommy Tadpole.[/spoiler] [spoiler]There were a couple of narrative loose ends/ open questions for me where I would've loved a bit more information. They stood out to me a bit, but considering how long this game was in development and that time and budget aren't infinite, they're easy enough to forgive.[/spoiler] Gonna go and replay Tangle Tower now!
Me encanto la historia, la banda sonora y obviamiente los diseños de cuartos como tambien de personajes. mi personaje Fav es simetrica la amo. Me agrada que sigan agregando mas lore acerca de las familias.
WOW! This game was soooo GOOD! The Grimoire games keep getting better and better with every new game. A lot of the things I liked less about Tangle Tower got improved in this one: A more believable story of the murder and better reasoning of the culprit, a more elaborate ending + a brief look to the future of the remaining characters (after the events) + the time it takes to finish the game went up quite a lot (basically doubled) which was fun! I'm very happy the developers went in a slightly different direction with the story this time as the last two games both had the 'searching for mystids/cryptids' storyline which felt a little too similiar. This time they went with an object rather than an animal/creature as the main thing, which felt refreshing! The artstyle, location- and character design were truly GORGEOUS, as to be expected from this incredible team! + The voice acting was so GOOD as well, they truly made the characters come to life! This game and its story felt the most complete and real out of all the Grimoire games so far! I also prefer how this game had very subtle mentions of characters from the earlier games, the ending was so sweet as well! As mentioned earlier the Secrets of the swamp and Tangle tower were a LOT of FUN, but they did feel a little too similiar. This game felt very refreshing! I also really liked the new characters and prefer the characters not all having the same 3 last names haha (Fellow etc.). My only complaint would be that the talking to the characters went on a little too long at times. Asking them about all the suspects, clues and asking the questions was fun, but seemed to take just a bit too long as I felt my attention slither away every now and then and found myself clicking through some of the dialogue to get through everything. I prefer puzzles and looking around the locations for clues over dialogue, so this felt just a bit unbalanced. It would have been even more fun with a few extra clues or puzzles and a little less lenghty dialogue parts here and there. Still I am incredibly excited to see more!!! I'll be patiently waiting for the next game, whatever it may be!
I'm just now able to properly gather my thoughts and express how much I truly enjoy this franchise. After Tangle Tower, I was left wanting more. More puzzles! More stories! More fun voice acting! Let me just say, The Mermaid Mask certainly delivered. and then some! I only wish we had more puzzles to solve, which is literally my only complaint. I was extremely happy with everything else in the game. Really cool and unique character designs as always (and suuuper cool environments wowee!), super fun dialogue and great voice acting. OH! I love the updated animation for when each suspect is telling their pov! Really nice touch. I don't really want to say much other than that, so that people can experience the game on their own. I look forward to future games in the franchise! (please please please make more please)
中文翻譯有點爛 在關鍵處會影響解謎 除此之外很好玩
An amazing mystery with a gorgeous presentation. Witty and clever writing, lovable characters and a compelling culprit.
incluso mejor q el anterior.......... CINEMA
Amazing. Worth all the wait. Small aside the achievement for finishing the game didn't trigger on my playthrough.
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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
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