The Mermaid Mask Release Date, Platforms, and What It Is

Eight suspects, one sealed room, and a body at the bottom of the sea — that’s the shape of it. The wait was long and the game shipped under a name it wasn’t announced with, but it landed on every promised platform on the same day, with no staggered console rollout to sit through.

Release date, platforms, and developer

The PC build runs on Windows through Steam, and Nintendo owners are covered on both Switch generations, with the Switch 2 version listed apart from the original Switch release.

The locked-room murder aboard the Mortuga Submarine

Captain Magnus Mortuga is found dead inside the Illusion Theatre, a sealed room aboard his own submarine, lying beside an ancient stone cauldron with a single fatal wound and no weapon anywhere in sight. The sub is moored in pitch-black water off Silkwirm-on-sea, a fishing town that was abandoned long before any of this started.

Mortuga was a recluse, and the stories about him grew taller the longer he stayed under. Some said he was an immortal time-traveller; others swore he was a vampire, cursed to stay hidden beneath the waves. What’s left behind is a crew of eight suspects, each more eccentric and harder to read than the last, and a door that shouldn’t have let anyone in or out.

You play Detective Grimoire, with his partner Sally Spears alongside you. The detective is called aboard by Sinthia Seafoam, who takes over as captain the morning after the murder — and hiring you doesn’t get her off the hook, because she’s a suspect like everyone else. Whether the crew sails on or sinks comes down to what you work out.

How the investigation plays out

The puzzles are tricky by design and they gate your progress rather than sit off to the side as optional busywork. Expect to be stuck for a bit, and expect the game to enjoy that.

Where it sits in the Detective Grimoire series

This is the fourth Detective Grimoire game, and it comes from the studio behind Tangle Tower and Crow Country. The handcrafted art, the sharp humour, and the puzzle-driven structure all carry straight over from Tangle Tower, which is the closest thing to a template here.

Length is the one expectation worth setting. Early estimates put The Mermaid Mask in Tangle Tower’s four-to-six-hour range, while SFB Games says its own game runs at least twelve hours and probably more.

Why you’ll still see The Mermaid’s Tongue

The game spent years in development as The Mermaid’s Tongue, which is why it still surfaces under two names. Old trailers, old links, and the original website all carry the earlier title, and the store listing kept its place through the change — nothing forked off and nothing was replaced.

So if you wishlisted it, bookmarked it, or argued about it in a thread under the old name, all of that still points here. The rename changed the words on the box, not the game inside.

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