Black story (La historia negra de Peter P. Peter) (1971)

Peter is a widower who writes crime novels, signing as Peter P. Peter, and is about to marry Beatriz (Analia Gade), a widow who proves to be a ruthless woman who makes his life miserable. As an expert in inventing crimes committed by his characters, he imagines a plan to get rid of his new wife. The trouble is that she also plans to kill him.