With Halloween just around the corner, it's time to celebrate the scariest episodes of TV that ever aired. 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!