Marcus Brody is a troubled engineer, returning to the BRASS-2 located in the depths of the South Pacific, hoping to pick up where he left off. He quickly finds comfort in the new doctor and is happy to reunite with old friends. All seems well until one fateful morning, Marcus is awoken by an emergency and scrambles to action. He does his best to warn and evacuate everyone but as he makes his way to his submarine he begins being haunted by figures of his past and starts seeing visions and hearing voices of unimaginable horror that begins destroying the station around him. He wakes up in the partially flooded control room with a small group of survivors. Everyone must work together to escape alive and Marcus Knows the station and its secrets better than anyone. They're forced to fight tooth and nail through every room. Each step they take drives Marcus closer to the evil plaguing his mind.