Marcel Andouillé is accused of having killed a young biker, Jacques-Emmanuel Sorède, belonging to a gang of bikers who trained near Andouillé's home. The noise bothering him more and more.
Edmond Marquet is charged with attempted murder of Alain Tenot. The latter had an affair with his daughter Catherine. Firmly opposed to this affair, Marquet sequestered her. Worried, Alain comes to the Marquets' house.
Shortly before a robbery, Michel Lambert is spotted by the police. Realizing the trap, he rushed into the neighboring apartment and took Mrs Petrovic and her two children as hostages, as well as a neighbor who was there.
