Here are the episodes that left a lasting mark in your nightmares. Some come from genre shows that always offered a scare or two and others come from shows that had no business treading into the horror genre but did so anyway.

And a special note: this list is deliberately not including episodes of anthology shows, so no 'Twilight Zone,' 'Tales From the Crypt,' 'Night Gallery' and so on. After all, we could fill this entire list with 'Twilight Zone' episodes. But we digress. Onto the list!

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    "Sylvia"

    'Little House on the Prairie'

    It may seem weird for a show as generally harmless and kid-friendly as 'Little House on the Prairie' to have a spot on this list, but it more than earned it with "Sylvia."

    A two-parter than aired halfway through the show's seventh season, the episode deals with a terrifying, black-clad man in a mime mask (!) terrorizing and raping (!!) a young girl named Sylvia, impregnating her and causing all kinds of additional stalking and horror movie shenanigans. Watching a gentle show about people trying to make a living on the American frontier transform into a low-rent, grossly tacky '80s slasher flick is odd (and a little hilarious) today, but for the countless oblivious kids who were tuning in to see what the Ingalls clan was up to that week, it was downright traumatizing.

    NBC