As If It Were Raining (1963)

Down on his luck writer Eddie Ross (Eddie Constantine) comes to the aid of a young woman seemingly being accosted on the street. His heroism nets Eddie a job with an odd underground figure known only as Martinez. The boss gives Eddie enough money to rent an apartment, buy new clothes and get a pet chimp(?!). The down side of the job is that Eddie finds himself becoming an enforcer for Martinez's blackmailing schemes. Teaming up with the young lady he saved earlier, Eddie sets out to to find out what hold Martinez has over her and what the jig is.