Thalassa is a single-player first-person psychological drama set in 1905. You play as Cam, a diver aboard the research vessel "Thalassa." A tragedy occurs while raising an ancient Spanish galleon from the ocean floor.

To recover from the incident, you temporarily leave the ship, only to learn later that it mysteriously sank, and none of your crew survived. Now, you must return to the "Thalassa." With the help of your dive supervisor, Bailey, who will guide you from the surface, you'll explore the wreckage, gather clues, and uncover what transpired on board in the final moments before the disaster.

Immerse yourself in an atmospheric story of grief and self-discovery unfolding aboard the "Thalassa."

The game delves into the complexity of human emotions. Unravel the tangled relationships among your crew members. Discover what burdened each member of the "Thalassa" crew and how they coped with the tragedy. The pain of loss can take many forms while life continues on.

As the last remaining diver of the "Thalassa," you must return to the ship, now lying at the bottom of the ocean. Navigate through the mesmerizing locations of the sunken vessel, search for clues, and reconstruct the chain of events leading up to the catastrophe.

Experience the profound stillness of the ocean as you move through the flooded cabins of the "Thalassa." Tools you find will help you clear obstacles and explore the entire ship.