I Saw What You Did

“Don't laugh little girl, better run for your life. The man you were talking to, has just murdered his wife!”

Libby (Andi Garrett) and Kit (Sara Lane) are teenage friends who pass an evening making prank phone calls, dialing strangers to whisper that they know what they did. One of the numbers belongs to Steve Marak (John Ireland), a man who has just killed his wife. William Castle sets the pair against Marak and Amy Nelson (Joan Crawford), the woman living near him, with the same phone in everyone's hands.