The Prowler (1951 film)

The Prowler is a 1952 blackandwhite thriller film noir directed by Joseph Losey that stars Van Heflin and Evelyn Keyes. The film was produced by Sam Spiegel as S.P. Eagle and was written by Dalton Trumbo under a pseudonym.

Obsessed, he woos her despite her initial reluctance and the two begin an adulterous affair. Webb finds out about an insurance policy on the husbands life. He dreams up a scheme in which a phantom prowler would be a good scapegoat if Susans husband should happen to die mysteriously. After becoming a prowler himself, Webb investigates and then commits the murder, making it look like a tragic accident with he and the husband shooting at each other as each suspected the other of being the prowler. Webbs ruse fools a coroners jury, thanks in part to both Susan and Webb testifying that they didnt know each other prior to her husbands death. Susan initially suspects Webb of foul play, but becomes convinced of his innocence and subsequently marries him.Shortly after the wedding, Susan informs Webb that she has been pregnant for four months. This is problematic because the date of the childs conception would prove the two had lied in their testimony to cover up their previous relationship, and would thus suggest that Webbs killing of Susans husband had not been an accident. The two run away to a ghost town named Calico to have the baby without anyone back home knowing. Susan goes into premature labor and Webb finds a doctor, Dr. William James Wheaton Chambers. Susan realizes that Webb intends to kill Dr. James to preserve their secret, so she warns the doctor who then escapes with the newborn. ........

Source: Wikipedia