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Kit (Sarah Lane) and her best friend, Libby (Andi Garrett), are two teenage girls bored while baby-sitting. To pass the time, they make prank phone calls, telling the person on the other end of the line, "I saw what you did, and I know who you are!" It's all in good fun, until they call a man (John Ireland) who just murdered his wife and buried her in the woods. Convinced they actually do know his secret, he becomes determined to find out who they are and silence them forever. Wikipedia