Overview
Mysterious Intruder is a 1946 American mystery film noir based on the radio drama The Whistler. Directed by William Castle, the production features Richard Dix, Barton MacLane and Nina Vale. It is the fifth of Columbia Pictures' eight "Whistler" films produced in the 1940s, the first seven starring Dix.
Plot
Edward Stillwell, the aged proprietor of a music store, hires private detective Don Gale (Dix) to find Elora Lund, a then 14-year-old who vanished seven years ago at the time her mother died. Stillwell can only pay $100, but hints mysteriously that finding Lund could make Gale a rich man.
A young woman claiming to be Elora Lund shows up at Stillwell's shop, supposedly in answer to his newspaper advertisement. Stillwell tells her that her mother gave him some "odds and ends" to sell; he discovered something very valuable among them, but refuses to give her any details until he telephones Gale. Meanwhile, Harry Pontos sneaks into the basement and finds a package marked as belonging to Lund. He grabs it, then stabs Stillwell to death and kidnaps "Elora Lund". Gale informs the reporters at the murder scene that the woman is not Lund. The news results in her release unharmed.
Gale goes to see her; her real name is Freda Hanson, and she is Gale's accomplice. From clues that Hanson is able to provide, Gale retraces her steps and finds the house occupied by Pontos. Finding Pontos drunk and passed out, he looks around, but just then, Police Detectives Taggart and Burns bang on the door. Pontos awakens, grabs a gun and a shootout ensues. Gale sneaks away, but is seen by a neighbor and loses a shoe in the process.
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