Four card players meet in a bar every night. The Journalist - Daniel Auteuil, The Doctor - Richard Bohringer, The Tradesman - Philippe Leotard and The Professor - Claude Pieplu. The bar is run by The Brothel Keeper - (Jeanne Moreau) and is frequented by working girl Lotte (Fanny Ardent). Michel Piccoli is the downtrodden barman Le Paltoquet. When there is a murder in a nearby hotel they all become suspects, but which one is a killer? The Inspector (Jean Yanne) casts his expert eye over the assembled suspects. Who could it be?