
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% | — | $1.1M |
| $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 1527 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
Reviews
It's just good.
Look, I don't really write reviews, ever. But the Detective Grimoire series has been such a joy that I need to add my own voice to the praise this game has been receiving. I found the DG series last year, or the year before(?) with The Tangle Tower and fell in love; the music, the humor, the attention to detail, the story, the visuals and, most importantly, the characters. Grimoire and Sally carried me through the Tangle Tower on a whirlwind of laughs, tender moments, gripping intrigue and a surprising amount of ominous, tense moments where I found myself on the edge of my seat. It was a fantastic experience that I've been chasing the feeling of since I beat it. Then I played the previous game in the franchise, which is also on Steam and something I highly recommend if your newest dose of SFB's particular brand of genius wasn't enough with the latest entry. To look back and see how far the franchise has come, how far the studio as a whole has come, brings such joy and wonder to my heart. Now the newest game has come out and I can quite honestly say that it was worth the wait. The Mystery of the Mermaid's Mask was one that had me utterly enthralled from the moment I started playing to the final reveal and showdown. I'm not ashamed to admit that, for all I made connections and solved a few key bits of the story a good bit before I had the option to confront people about their secrets, the *actual* inciting mystery and the culprit at the end managed to, if not blindside me, then completely upend my own personal theories on who the culprit really was! If you are hesitating on buying this game, don't, it's worth every penny I spent on it and if you haven't played the previous entries do yourself a favor an go and get those as well, play them all and know that you have my envy that you get to experience them all for the first time yourself. P.S. To the developers at SFB Games... I still remember that Sally called Grimoire Cute or Handsome when they first met in the random dialogue you could get. Still no romance? I wont forget this...
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
Very good art and story! Has some connections to previous games in the series, but not enough that you will feel you are missing anything if this is the first one you play. Puzzles aren't too difficult. Voice acting is great!
Another fantasist Grimoire mystery! I highly recommend
You guys have done it again! The Mermaid Mask from start to finish had me on the hook. Always love to hang out with Sally and Grimoire, hear the witty banter, the writing is intense, the puzzles are fun, the music is incredible! I highly highly recommend playing for yourself and go play the other 2 titles as well! Can't wait to see what you guys do next!
AMAZING writing, characters, and mystery! love the Grimoire games but this easily moved up to my favorite.
If you enjoyed Tangle Tower, then you will love this! Everything awesome about the previous game plus even more fun characters and cool designs! C:
Another delightful mystery-puzzle game from SFB! It keeps the charming dialogue and enjoyable puzzles from Tangle Tower and manages to dial up the atmosphere quite effectively. My only real complaint is that the puzzles can be a bit on the easy side, but the overall puzzle of the mysteries helps make up for that. Thoroughly enjoyable and well-worth buying.
Another incredible game by SFB! Beautiful voice acting, intriguing story line and another set of curious characters. You can feel the depth of work that has gone into creating The Mermaid Mask.
The voice acting was so nice this game, as per usual! I enjoyed the silly 3D models they've got this time around. Some easter eggs that tie back to the previous games was a nice touch. Looking forward to more mysteries to uncover!
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
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