WATCH: Brothers convince sister of zombie apocalypse after wisdom teeth surgery

Three mischievous older brothers are making headlines after they convinced their little sister – who'd just had wisdom teeth surgery and was high on painkillers – that a zombie outbreak had struck Washington, D.C.

According to USA Today, Cabot, Hudson and Barrett Phillips got their friends, family and dentist to help with the epic prank, which was captured on videoThe viral clip, which was posted to YouTube on April 11, already has more than 800,000 views.

The fun starts on the car ride back from the dentist's office with a fake Centers for Disease Control and Prevention radio bulletin warning of "high fever, nausea, death and even cannibalism." The sister, Millicent, struggles to make sense of it all.

"We have guns," she says, frustrated, as her brother grabs a garden hoe to use as a makeshift weapon. "Why are you putting garden equipment in the car?"

Later, when asked which pet they should save, she angrily shouts, "The cat, you idiot!"

"We just didn't anticipate how expressive she would be, and how many one-liners she'd produce — even when terrified and in a drug-induced state," Cabot Phillips told USA Today.

>> Click here to watch the viral video