Manu, a small-time thief living in the Paris suburbs comes home from the cinema to find his mother lying dead in a pool of blood in her appartment, a knife at her side. The building caretaker sees him with the murder weapon and phones the police. Manu flees the scene and finds himself the prime suspect in her mother's murder. He has no choice but to find the murderer and retrieve the knife with his fingerprints.
Clash is a graphical adventure game. The player uses icons to move around town, question Manu's former friends and acquaintances, search for clues and escape the police. The game has a time limit (8 hours and 15 minutes); it can only be solved by carefully talking to almost every character in the game, taking notes and making a map of the city.