An impossible locked-room murder: Captain Mortuga lies dead beside an ancient cauldron aboard the world’s strangest submarine, crewed by sketchy suspects. 

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