The Hangover heartthrob, 39, has bulked up by around 40lbs for his role in Navy SEAL drama American Sniper.
As well as gaining weight, the gorgeous actor has also been gaining a pretty impressive beard. There's no word yet on whether that's for the movie as well.
Bradley will play Navy Seal Chris Kyle in the movie, based on Chris' autobiography American Sniper. It co-stars Sienna Miller and is directed by Clint Eastwood.
Chatting to Ellen DeGeneres back in February, the actor said: "I feel I have to be somewhat in the same vein as [Chris] was as he was a big guy."
Bradley's weight gain hasn't gone totally smoothly, however, as he recently recounted a slightly embarrassing incident at the White House after misjudging just how much weight he had gained.
"I had gained 15lbs in four weeks and nothing fit me anymore," he said. "I decided to wear the tuxedo I wore to the Golden Globes and just threw it in my bag and brought it to Washington DC. I'm getting dressed and ten minutes before I'm supposed to go, I realise the pants don't fit. I was laughing thinking, 'Hilarious, I'm going to meet the President [like this].' I had to go commando. There was no room at all. They were crazy town tight."
Bradley's model girlfriend Suki Waterhouse was also at last night's Met Ball but the couple walked the red carpet solo.
Got an iPad or iPhone? Reveal Mag is specially designed to fit!
All the Met Ball 2014 gala pictures below:
Copyright: WENN Andres Otero