Can a burger actually give you nightmares? That’s what Burger King set out to prove with an unusual research study for its latest Halloween limited time offer: the Nightmare King. Based on the unique build of the sandwich, which consists of a mix of proteins like bacon, chicken and beef, plus cheese, the hypothesis was that this new burger could cause nightmares. So, Burger King turned to science to validate this. And the results of the clinical study prove that the Nightmare King increases your chances of having nightmares by 3.5 times.