By Jessica Derschowitz
Updated February 17, 2016 at 06:08 PM EST
Credit: ABC

Ben Affleck officially becomes the new resident of Wayne Manor when Batman v Superman: Dawn of Justice arrives in theaters next month, and the actor says he received advice from two previous Dark Knights about donning the hero’s famous cowl.

Speaking on Good Morning America, Affleck shared the guidance he got from George Clooney and Christian Bale.

“I talked to Clooney and he gave me some advice which is not repeatable,” Affleck joked during the interview. “And I talked to Christian, who just told me to make sure I got a zipper in the suit, which was valuable, practical advice as it turned out.”

Clooney donned the batsuit for 1997’s Batman & Robin, while Bale played the Caped Crusader in Christopher Nolan’s acclaimed trilogy: Batman Begins (2005), The Dark Knight (2008), and The Dark Knight Rises (2012).

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Appearing in the GMA interview alongside his Batman v Superman costar Henry Cavill, who plays the Man of Steel, Affleck noted he had to get in fighting shape to play Bruce Wayne/Batman — but not quite as much as Cavill did to play Superman.

“I saw the first movie he was in and I was like, ‘Wow, I don’t know if I’m going to be in quite that good of shape,'” Affleck said of Cavill. “He has definitely set a high bar but he also has to be in that high bar because he’s, you know, an alien.”

He added, “I figured I had a lower bar to reach because I’m just a man after all, but I ended up putting on about 20 pounds of muscle, which is really hard to do in my advanced age.”

Batman v Superman: Dawn of Justice arrives in theaters on March 25, and Affleck says he’s proud of what fans will see when they head to theaters.

“I really care about [the film] and I want it to do well,” he said. “I feel like I got to work with some really talented people and I’m really proud of what we were able to do.”

Watch the full interview below.

Batman v Superman: Dawn of Justice

  • Movie
  • PG-13
  • 151 minutes
  • Zack Snyder