Le Samourai (1967)

Jef Costello, a Paris-based hit man who is meticulous in his work, is preparing for his latest job, he not knowing his client in working through an intermediary. That preparation includes setting airtight alibis, one with his girlfriend Jane Lagrange, and scoping out his entry and escape from where the hit is to take place, the office at Martey's nightclub - the target Martey himself - without anyone really noticing him. Although he is able to carry out the hit, it is not as clean as he would have wanted. In the police rounding up several hundred suspects in the immediate hours following the hit, Jef is surprised by the outcome of his questioning, he being released against certain odds working against him. Although the statements by the witnesses at the club who could have seen him being inconclusive as to him being the murderer, the police commissioner is still working on the high probability that Jef is the man for who they are looking, and as a result places much of his resources in placing Jef under secret surveillance. In Jef concluding the transaction with the client through the intermediary, things again do not go according to what Jef would have expected or wanted. As such, Jef believes he has to find out the identity of the client and/or his/her reason for wanting Martey dead, all while eluding the police, who he knows is pursuing him.