The steamship Atlantica makes way to Boston, but dark shadows trail the ship, staying just out of sight beneath the waves. The ship’s passengers seem unnaturally fixated, staring out to sea with a silent, desperate longing. The investigators’ dreams are plagued by eerie underwater nightmares. And now, a passenger has been murdered. Suspicion, hidden loyalties, and devious strategy rule the day! Unfathomable puts the players in command of a steamship, but not every player can be trusted. While monstrous Deep Ones stream forth from the crushing ocean depths, any player could secretly be a nefarious cultist or a horrifying hybrid Deep One. The investigators must take care not to turn their backs on anyone—it will take all their cunning to save their ship from a watery grave. Battle swarming Deep Ones, uncover the traitors, and steer the Atlantica safely home in Unfathomable! STRATEGY HORROR GAME: Not all is well on the steamship Atlantica: a foreboding sense of dread, shadows under the waves, and a ritualist murder have the crew and passengers on edge. Now they must work together to get the ship to shore, but not all aboard are what they seem. HIDDEN TRAITOR GAME: Unfathomable is a hidden traitor game where players assume the roles of the passengers and crew of the Atlantica. They work together to fight off beasts and perform repairs to the ship. However, some of the players are secretly cultists determined to sabotage the heroes. WORK TOGETHER, OR NOT: As beasts emerge from the depths and events occur around the ship, players will need to play cards into a pile in order to meet specific requirements. However, the cultists, working to sabotage the others, may secretly play the wrong cards in order to fail the events. ARKHAM HORROR GAME: Set in the Arkham Horror Files universe, Unfathomable takes place many years before the board and card game but features the same rich lore and offers a full cast of new characters. Fans will be excited for an all-new game experience in their favorite horror universe. NUMBER OF PLAYERS AND AVERAGE PLAYTIME: Unfathomable is a hidden traitor board game for 3 to 6 players and takes 120 to 240 minutes to play.