When the comedy Neighbors — which stars Seth Rogen and Rose Byrne as Mac and Kelly Radner, a couple with a baby whose lives are upended when a rowdy fraternity led by Zac Efron’s Teddy Sanders moves next door — was originally conceived, Rogen and Efron’s characters were written as hate-filled rivals from minute one. But after hearing the two stars’ obvious chemistry at an early table read, it became clear that having them bond before developing their rift was essential. “We realized how much we would get along, and how funny we could be together,” Rogen, also a producer on the film, tells TIME. “Because of that, we extended the honeymoon period.”
In the film, which hits theaters May 9, the disparate lifestyles of the new parents and the fraternity lead to subterfuge and all-out war, including sexual schemes and violent booby traps all intended for maximum laughs. But first, Mac and Kelly see the last vestiges of their youth in the fraternity’s booze- and drug-fueled bashes, and integrate themselves into the perpetual party next door.
For Rogen, now is the time to deal with the issue of trying to sidestep adulthood — however unsuccessfully. “I’ve been the star of almost every movie I’ve had some hand in creating, and because of that, I’ve always made movies that focused on people [my] age,” says Rogen. “Now, I’m 32, I’m married, and a lot of my friends have kids or are having kids. So it only seemed natural to make a movie that embraced that.”
Neighbors marks an even greater turning point for Efron, with the 26-year-old heartthrob top-lining (along with Rogen) his first adult comedy, and also for the first time playing a villainous character. “Mostly I was just excited,” says Efron. “The caliber of work when you’re on set with [guys like this] is really smart and funny. You have to be ready for anything. The hardest part [for me] was finding some heart in this character, because he does a lot of really heinous things, and he’s nothing like me. This is the furthest character from myself that I’ve ever played.”
Hinging as it does on the chemistry between the two leads, the film found a bonding point in an early party scene where a wasted Mac and Teddy compare Batman impressions. The improvised scene sets the stage for the battle to come, making the film’s central feud not just a disagreement between neighbors, but the result of a perceived betrayal between two people who, if even for just a fleeting moment, cared about each other.
The scene evolved from a desire to find a funny way to depict the difference in age between the two. “We were trying to find slight variations [in our tastes],” says Efron, “small generational differences in things like video games.”
“We knew we wanted them to talk about the difference in their generations,” says director Nicholas Stoller. “I noticed Zac doing Batman impressions [on the set]. He does a really good Bane. So we were shooting the scene with all these jokes we’d written, but it felt forced. If they don’t bond in that scene, then the movie won’t work. One of them started talking about Batman, and I yelled from behind the monitor, ‘Just compare Batman impressions.’ I’m rarely sure that I got something until I’m cutting the movie, but [after that], I was like, that’s gonna be in the movie. That’s kinda magical.”
“It perfectly demonstrates the generational divide between the guys,” says Rogen, “but it also shows that if circumstances were different, they would really get along.”
For Efron, the set’s free-flowing nature was liberating, if not a bit stressful.
“In a film like this, in this genre, it’s instrumental to be able to be on your toes and stay in character,” says Efron. “Improvising with certain people brings out the best in you, and the advantage here was, these guys are incredible at it. It’s a challenge, because you don’t know what you’re going to say, so you literally just have to be. It’s freeing in a way. I had a blast.”
Now that he’s been seduced by the improvisational comedy bug, Neighbors could represent a turning point in Efron’s career: audiences are likely to wonder if he'll join the likes of Rogen, Paul Rudd and more in becoming a staple of the modern comedy.
“I could see that happening, for sure,” says Efron. “I think it’s all [about] who you surround yourself with. I’m really lucky to be in a movie with these guys, and I would jump at the chance to do it again.”