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Free pizza? No one in their right mind would turn that down.
And that's exactly what happened when these Korean pranksters set up a promotional stand in the streets of Seoul offering complimentary slices for people to help themselves to.
Under the guise of Papa Johns reps, YouTube pranksters JKTV placed the attractive offer in the middle of a busy pedestrian area.
But unbeknownst to those stepping forward to open the pizza box and take a piece, a man's hiding underneath the cardboard lid -- in a Joker mask!
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Needless to say, the results are hilarious, with the majority of people jumping out of their skin at first sight of Batman's scary nemesis. Check out the fun below!