Shia LaBeouf says he trained intensely for two months and gained a whopping 50 pounds to prepare for his role in the prohibition-era gangster film Lawless.

LaBeouf told ET at a screening of the movie last night in New York that he was pushed hard by co-stars Tom Hardy and Jason Clarke — who play his siblings in the film — to “train harder than anybody who showed up for this film.”;

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“There’s a fabric of the family that needs to exist, he explained. “So had I showed up in my fighting weight — which is 130 — next to Hardy I wouldn’t have looked like I was related. So I shipped out at 180 and he dropped his weight. And Jason upped his weight and we all tried to level out.”;

Lawless — also starring Gary Oldman, Guy Pearce, Jessica Chastain,  Mia Wasikowska and Dane DeHaan — tells the story of the bootlegging Bondurant brothers in Depression-era Virginia. The government tries to persuade the brothers — played by LaBeouf, Hardy and Clarke — to give them a share of their profits in exchange for immunity from arrest.

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Chastain revealed there was plenty of “masculine energy”; on the set that she didn’t mind, but one day she admits she was glad to see another actress show up. “After a few weeks of filming, as much as I love the guys, the first day Mia Wasikowska was there, I ran into the makeup trailer and I threw my arms in the air and I just yelled out, “It’s a girl!’ I was so happy.”;

Watch the video to hear DeHaan talk about how it was his “dream come true”; to work with the talented cast of Lawless, which hits theaters August 29.

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