The October Man

The October Man is a 1947 mystery filmfilm noir starring John Mills and Joan Greenwood, written by novelist Eric Ambler, who also produced. A man is suspected of murder, and due to the lingering effects of a brain injury sustained in an earlier accident and after intense police investigation, he himself begins to doubt whether he is innocent or not.

He starts a new job as an industrial chemist and gets a room in a hotel. When he reluctantly accepts an invitation for a night out, he meets Jenny Carden Joan Greenwood, the sister of his coworker, Harry Patrick Holt. They begin seeing each other quite regularly. Things reach the point where he confesses he wants to marry her, but he tells her he wants to be sure he has fully recovered first.Molly Newman Kay Walsh, one of the other hotel residents, asks to borrowfrom him, a rather substantial sum. As he doesnt have that much on him, Jim goodnaturedly writes her a cheque. She is found strangled the next night. Wilcox Jack Melford, the married businessman Molly had been seeing, has an alibi. Jim admits to have been walking in the vicinity of the murder site that plus the cheque and his head injury make him the prime suspect. Police Inspector Godby Frederick Piper suspects he was another of Mollys boyfriends and that, after falling in love with Jenny, he wanted to rid himself of a possible blackmailer. ........

Source: Wikipedia