Cyril Ritchard plays artist Mr. Crewe
Blackmail on IMDB
Scotland Yard Detective Frank Webber (Longden) escorts his girlfriend Alice White (Ondra) to a tea house. They have an argument and Alice leaves with Mr. Crewe (Ritchard), an artist whom she has earlier agreed to meet. At his studio, Crewe sings and plays "Miss Up-to-Date" on the piano. Alice innocently flirts with the artist. He convinces her to try on a dress then attempts to assault her as she is changing. Alice grabs a nearby bread knife and stabs him to death.
Alice leaves after attempting to conceal any evidence of her presence in the flat. She has, however, unknowingly left her gloves behind. The next day Frank is assigned to the case and finds one of the gloves. He realizes the glove belongs to Alice and visits Alice at her father's shop. Local petty thief Tracey (Donald Calthrop), who saw Alice at the artist's flat earlier, interrupts the two and attempts to blackmail the couple. Frank tells Tracey his attempt will fail.
The tables are turned when Tracey becomes the chief suspect after the artist's landlady identifies him as being at the scene of the crime. Tracey flees and is pursued by the police. He clambers onto the domed roof of the British Museum and is killed after falling through a glass panel of the dome.
Alice feels compelled to confess she killed the artist and goes to Scotland Yard. She attempts to talk to the Chief Inspector but is escorted out by Frank.
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