Un Flic (1972) on Netflix

A gang formed by Simon, Paul Weber, Louis Costa and Marc Albouis heist a remote bank during a stormy afternoon. However Marc is seriously wounded and they leave him in a clinic after hiding the money in a sophisticated scheme. Meanwhile the cold Police Inspector Edouard Coleman is investigating the murder of a woman and his informer, the travesty Gaby, tells about a shipment of heroin carried by the mule Suitcase Matthew by the train to Lisbon. Then Coleman heads to a nightclub owned by Simon, who is his friend, to meet his mistress Cathy. When Simon learns that the police force is tracking down the wounded thief in hospital and clinics and the dragnet will certainly find Marc, he goes with the gang and Cathy to kill him. Then Simon plots the robbery of Matthew's drug In the train using a helicopter. When Coleman intercepts Matthew, he does not find the drug shipment and believes that Gaby is not giving good information to him. But when Simon discover that Marc Albouis is dead, he connects him to Louis Costa and then to the unemployed middle-aged banker Paul Weber and Simon. They bug Simon's telephone and Soleman heads to confront his friend.