Mild spoilers for "Neighbors" ahead.

Once the great prank war between Zac Efron's and Seth Rogen's characters in "Neighbors" finally ends, the two share a very special, very shirtless bonding moment outside of an Abercrombie & Fitch store, attempting to entice passersby into shopping there.

When I spoke with Efron and Rogen, they shared the true story behind the scene, which was filmed in a real mall with actual shoppers walking by.

Though Efron is pretty much used to going topless for a role, this scene in particular made him feel a little embarrassed.

"Seth just took his shirt off and just started standing next to us. Literally, I think [director Nicholas Stoller] was like, 'Try to get people into the store,' " Efron said. "So customers would come by -- real, legit customers -- and we would just try to usher them in. And nobody would come in. It's so sad. Pretty much the whole scene was improv, but I was kind of embarrassed I couldn't get anybody in the store."

"Neighbors" opens in theaters on May 9.