People's horror of utility bills has been a trending topic on social media in Brazil recently, so for Halloween this year, Burger King has attempted to tap into this "fear."

In a campaign via David Sao Paulo, the brand is sending a discount voucher disguised as a utility bill to 10,000 fans. People can also view the "Whopper Bill" online and can send it to their friends as a prank. By accessing the WR code with a smartphone camera, people can redeem the bills for half price discount vouchers for a Whopper combo, valid only on Oct. 31. 

Besides the direct mail, the campaign features a 30-second video clip in which zombies as well as clowns (in a nod to BK's McDonald's-baiting work perhaps) are superseded by bills as the thing that terrifies people most.

"They’ll never forget ghosts, vampires or zombies," said Rafael Donato, creative VP at David in a statement. "What really scares the hell out  of Brazilians is a bill. So naturally, we couldn't resist. This is one bill they're never forget."