A new 2013 "Neighbors" movie trailer just went viral. Zac Efron, Dave Franco, Seth Rogen and Rose Byrne star in the new clip from the forthcoming flick.

Efron, the 25-year-old "Parkland" actor, also went shirtless for a new TV spot promoting the film, according to JustJared.

The TV ad begins with Rogen explaining the movie's concept to viewers. A shirtless Efton tries to butt in and talk about his character, but Rogen tells him to shut up and say one funny line.

"That I should stand here with not shirt and keep my mouth pretty shut," Efron said in response to Rogen's request in the commercial.

[For the video, click HERE.]

But though Efron is mostly seen but not heard in the TV spot, he plays a big part in the new trailer with Rogen.

Entertainment Weekly reported that the trailer shows Rogen as the "uncool" guy. Instead, the carefree funnyman becomes a surburban dad, who moves into a nice home with his newborn baby and wife, who is played by Byrne.

But, of course, Rogen makes the audience laugh while fighting with next-door neighbors and frat boys, Efron and Franco. Efron flaunts his buff biceps in the clip, and proves to have some comedian chops as well.

The film hits theaters on May 9, 2014.

Going to see "Neighbors" when it comes out? Check out the trailer and tell us what you think in the comments section below!