By Joseph Martinez -

Zac Efron and Seth Rogen showed up at the premiere of the Frat vs Family comedy, “Neighbors” on Monday night (April 28, 2014) in Westwood, CA. Donning gray suits, the co-stars obliged the screaming fans as they made their way to the Regency Theatre shaking hands, signing autographs and posing for photos.

Seth Rogen, Zac Efron and Rose Byrne lead the cast in a comedy about a frustrated young couple who are forced to live next to a fraternity house after the birth of their newborn baby and face unexpected difficulties. The rowdy comedy was directed by Nicholas Stoller who's previous directing credits include "Get Him to the Greek" and Forgetting Sarah Marshall"

Interestingly, Seth Rogen was not a big fan of  Zac Efron prior to the making of the film. Rogen revealed to People.com, "I was expecting to not like him very much when I first met him," Rogen, 32, told PEOPLE with a laugh at the movie's premiere. Rogen adds: "I was proven very wrong because he's a sweet, nice guy … He was just so nice, cool and very self-aware and self-effacing and endearing, and all those things that make someone hard to hate." 

Efron appeared to be in very good spirits at the event in spite of reportedly getting hacked. According to USA Today the hackers stole his personal assistant's identity and tried to obtain photos of the star from a USA TODAY photographer. "Hi I'm Zac's assistant," wrote the hacker, sending a text personally to one of USA Today's staff photographers. "He was wondering if you can send a copy of the photo shoot you took of him for USA Today. My email is [redacted]." Efron doesn't seem to worry about it too much and shrugs it off but states that this kind of thing happens pretty often.

Nevertheless, all was well on the red carpet that was attended by fellow co-stars Seth Rogen, Christopher Mintz-Plasse, Dave Franco, Halston Sage among others.

The film opens nationwide on Friday May 9, 2014

For more info visit the official "Neighbors" at www.neighbors-movie.com

Visit an entire gallery from the event at PictureLuximages.com