The Boutaric city is blue; it is the last HLM block (social housing) from the 1950s in Dijon. In 2020, letters announcing the demolition fill the 146 mailboxes. In this context, a group of young people sets out in search of memories. They explore and film every nook and cranny of the building. As they try to solve the riddles posed by the last inhabitants, a mysterious creature awakens. A creative documentary that uses the codes of gaming to access reality and memory.