Zac Efron Gives Ellen DeGeneres a Lap Dance and Twerks

Courtesy of Warner Bros. / Michael Rozman

The actor plays a "bad behavior" version of Heads Up.

Zac Efron promoted his new movie, Dirty Grandpa, on Wednesday by playing a naughty game of Heads Up with Ellen DeGeneres.

DeGeneres told Efron that in honor of his film with Robert De Niro, she and the actor would be playing a "bad behavior" version of the game in which one person acts out whatever is on the card while the other person guesses the action. 

Efron proceeded to give DeGeneres a lap dance, mime Tinder-swiping, make out with his hand and twerk.

After the game, he said he regretted hesitating before attempting to twerk. "Whenever anyone tells you to twerk, just do it,"  said the actor.

DeGeneres then surprised Efron by revealing that she had been recording him on her Heads Up console, and treated the audience to a zoomed-in look at Efron's pants during the lap dance. Watch below.