12 Sleepwalkers Who Murdered People in Their Sleep

It seems like something right out of a movie like The Cabinet of Dr. Caligari or Side Effects: stories of men and women who killed people while sleepwalking. But it's a very real occurrence called homicidal sleepwalking, insane automatism, non-REM parasomnia, or homicidal somnambulism, in which a person unconsciously commits murder while sound asleep.  

Cases of sleepwalking murder have appeared as far back as 1846 (namely, the infamous trial of Albert Tirrell). Here are several such stories, pulled straight from the headlines.