The player controls a 'Class-D' personnel in first person, designated D as he attempts to escape an underground research and containment facility operated by the SCP Foundation amidst a total containment breach of its hazardous anomalies, designated 'SCP's. The game has a procedurally generated play area created from a random selection of pre-existing rooms and hallways that are strung together to create the facility which is played in. The game is played in 3D from a first person perspective and the protagonist is a human test subject labeled 'D' in an SCP Foundation facility devoted to containing and researching dangerous creatures called SCPs.

It is based on the paranormal fictional stories of the SCP Foundation website.