What was Seth Rogen thinking when he first met his Neighbors co-star Zac Efron almost 10 years ago? The two field a Twitter fan question via ET's Brooke Anderson -- with amusing results -- at the annual SXSW festival in Austin, TX!
RELATED PICS: Hollywood's Sexiest Shirtless Men
"He was very humble, and he seemed to be very aware of the fact that odds are I would be someone who hated him, which was very endearing to me," says Rogen with his trademark laugh.
In the outrageous Neighbors, Rogen and Efron face off in the story of about a young couple suffering (Rogen and Rose Byrne) from arrested development who are forced to live next to a fraternity house after the birth of their newborn baby. Christopher Mintz-Plasse, Dave Franco, Jerrod Carmichael and Ike Barinholtz also star.
Related: Efron -- I'll Accept MTV Movie Award Shirtless!
Directed by Nick Stoller (Forgetting Sarah Marshall, Get Him to the Greek), Neighbors moves into theaters May 9.