Today would be a good day to avoid Camp Crystal Lake.
Over 30 years ago, the world was first introduced to a boy named Jason Voorhees, who went from child drowning victim to homicidal maniac to unstoppable zombie in a series of 12 films.
Yep, we're talking about the "Friday the 13th" franchise, the series that made us think about hockey masks and serene campsites in a totally different way.
To mark the occasion, check out the gallery above to see what some of Jason's most memorable victims and adversaries look like now, including a teenage Kevin Bacon, a very young Corey Feldman and the telekinetic teen who took him on in Part VII.
And as a bonus, watch the ridiculously creepy (and very, very dangerous) prank one online trickster decided to play on people in his neighborhood.
Seriously, don't try this at home. We're surprised this guy didn't get hurt by one of his targets!
Note: The prankster says the chainsaw he was using didn't have any blades on it.
