Lady of Vengeance

Lady of Vengeance is a 1957 British film noir crime film directed by Burt Balaban and starring Dennis O'Keefe.
Plot.
When 21-year-old Melissa Collins (Eileen Elton) commits suicide, her guardian, the domineering American newspaper publisher William T. Marshall (Dennis O'Keefe), searches (in flashback) for a reason. He finds it in a letter he receives from Melissa, after her death. In this, she asks Marshall to take revenge on her lover, philandering musician Larry Shaw (Vernon Greeves), who caused her such pain he made life not worth living. Marshall hires criminal mastermind, Karnak (Anton Diffring), an avid philatelist. He promises him a rare stamp in exchange for planning the torturous murder of Larry Shaw. Meanwhile, Marshall's loyal secretary, Katie Whiteside (Ann Sears), attempts to calm her boss's obsessive desires for vengeance. Matters become additionally complicated however, when Karnak targets the wrong man.
Critical reception.
Dennis Schwartz writing in "Ozus' World Movie Reviews", called the film a "tedious noir crime drama about the insanity of revenge"; Leonard Maltin also described the film as "tedious"; and "TV Guide" noted, "the plot is very confusing, making it hard to follow this picture. Slack direction does little to help."