The Stranger Within (1974)

After eleven years of marriage, a young wife (Barbara Eden) finds herself pregnant but her husband (George Grizzard) had a vasectomy several years ago. Soon she finds herself drowning her food with salt, getting drunk on coffee, sleeping with all the windows open in freezing weather and speed reading books. Based on the novel TRESPASS by sci-fi maestro Richard Matheson and directed by Lee Philips. This mixture of horror and science fiction is quite effective in its potboiler way despite the inherent silliness of and execution of the plot. When Eden's character begins doing all those weird things, everyone around her is justifiably concerned yet no one seems to do anything about it except fret! Still, the story is engrossing enough to hold one's attention and the ending is pretty startling. With Nehemiah Persoff, Joyce Van Patten and David Doyle.