Event Horizon is a game set in the year 2047, where players take on the role of crewmembers in a UN-led fleet that is on a search and salvage mission to recover a state-of-the-art space ship, the Event Horizon. The ship had disappeared for seven years, and now that it's back, nobody knows where it has been. Players can choose to play as a commander or a specialist with different skills and abilities, and the game takes place on both the ships in the fleet and the Event Horizon. The game is one of exploration, resource management, and political agendas, and it includes elements of combat and violence.

The game is designed to be a megagame with lighter board game mechanics and prominent elements of negotiation and roleplaying. It is set in a near-future space horror setting, and players interact with each other and the environment as they explore the ships and the Event Horizon. The game is played across two rooms, with the first room holding the fleet and the second room holding the Event Horizon. There is severely restricted communication between the rooms, and the claustrophobic setting of the game leaves little room for the "grand scale of things" as each player is ultimately left alone to face what lies in wait on the Event Horizon.

Players must manage their resources and negotiate with each other to complete their objectives while dealing with the horrors that await them on the Event Horizon. The game has a heavy emphasis on roleplaying and negotiation, with players needing to use their skills and abilities to work together to overcome the challenges they face. Event Horizon is a game that offers players a unique and immersive experience, as they explore the depths of space and face the unknown horrors that lie ahead.