I once watched a Hollywood movie. A contract killer and a man who was ditched or thrown out by his girlfriend or wife settled in two side by side hotel rooms. The killer is getting ready for his job by fitting his telescopic gun through the window when the sad stupid man is knocking on the door of the killer, to get some sympathy.
Eventually the sad man got interest in this killing and in the gun. While the would-be victim entered the hotel (pathway visible through this window), the sad stupid man fired the gun. The victim had a security cover. He himself was dressed as a bodyguard while one of his bodyguard was dressed like him. But the sad man killed that "body guard" for his lack of skill and thereby fulfilled the contract. What is this movie? Please help.