Homicidal is a 1961 American horror-thriller film produced and directed by William Castle, and starring Glenn Corbett, Patricia Breslin, Eugenie Leontovich, Alan Bunce and Jean Arless.

The film follows a murderous woman in a small California town whose presence unearths secrets concerning a prominent local family.

She later gloats to a mute, elderly invalid named Helga (for whom Emily is a nurse and works for a wealthy family) of her deed.

The police investigate the crime and learn that the nurse was given the name of a local flower shop owner Miriam Webster, who has an alibi of the night of the murder.

When Warren's father died and he learned of the clause in the will that would have denied him his inheritance if it was known he was a female, he resumed the alter ego of Emily in order to kill and silence those who would know the truth about him.

[4] Based on the success of Castle's previous films, Columbia Pictures agreed to implement his concept for a "Fright Break.

"[6] This entails a 45-second timer which overlays the film's climax as the heroine approached the house harboring a sadistic killer.

A voice-over advised the audience of the time remaining in which they could leave the theater and receive a full refund if they were too frightened to see the remainder of the film.

[8] About 1% of patrons still demanded refunds, and in response Castle decided to spotlight the people who chose to leave by creating a "Coward's Corner.

[8] According to Castle, the gimmick worked "great," and that theaters earned an average of $20,000 weekly in box office sales, with only $100 in refunds.

[4] Multiple critics drew comparisons between Homicidal and Alfred Hitchcock's Psycho, released the year prior.

[6] Time magazine said: "Made in imitation of Hitchcock's Psycho, it surpasses its model in structure, suspense and sheer nervous drive.

The New York Times said "Near the end of Homicidal, yesterday's horror entry at neighborhood theaters, the disembodied voice of William Castle, the producer-director, announces a 'fright break', during which the economy-minded viewers may return their tickets for a refund ...

[6] In The Psychotronic Video Guide (1996), Michael Weldon referred to the film as an "incredible experience," and it has also been championed by filmmaker John Waters.

"[14] Douglas Brode echoed similar sentiments, remarking the film's "marvelous" pacing and sustainment of suspense.

[15] However, Glenn Erickson from DVD Savant wrote that the film was "a perfectly wretched movie, bad enough to make Castle's other hits seem like flukes".

[17] On July 19, 2016, Mill Creek Entertainment released the film on Blu-ray as a double feature alongside Castle's Mr.