AceShowbiz -

Ellen DeGeneres successfully made Zac Efron show off his "bad behavior." In the January 20 episode of "The Ellen DeGeneres Show", the 57-year-old comedienne invited the hunky actor to play a game of "Heads Up!" in which he's twerking and showing a lap dance.

The game required Zac to perform or make gestures in accordance with the words written on the screen of iPad Ellen was holding. Ellen, meanwhile, would guess what the words appearing on the screen were based on Zac's acts.

Zac went raunchy as the first words appearing on the screen were "Lap Dance." The "Neighbors 2" actor instantly drove the audience into hysteria as he gave Ellen a lap dance. The host smiled and made a correct guess of what Zac did.

The 28-year-old actor then acted as if he's kissing his hand to perform "Making Out." As Ellen made an inaccurate guess by saying "kissing" and "French kissing," Zac stuck his tongue out. She then made a correct answer after the actor asked her to try another word.

Next, Zac was asked to "Twerk." At first, the actor appeared to be shy as he paused and cursed after reading the word on the screen. However, he then coyly twerked and said, "Like that?" The audience cheered and applauded him as he's twerking next to a sofa.

The game got raunchier as the following word appearing on the screen was "skinny-dipping." Zac was laughing as the audience appeared to be excited to see him acting "skinny-dipping" onstage. However, the actor didn't go naked. He just acted out as if he's taking off his shirt and jumping into the water. Ellen successfully made a correct answer.

After they finished the game, Ellen asked Zac, "Why did you delay on twerking?" Looking embarrassed, the actor answered, "I don't know. Whenever anyone tells you to twerk, just do it." Later on, Ellen showed another fun side about the game - the iPad recorded any performance Zac did during the game including his lap dance. He said of the video of his lap dance playing on the big screen, "So happy to have that all the time."