Josh Brolin is lifting up his T-shirt to show me his stomach. This unsolicited flashing of the flesh is an attempt to demonstrate the effects of the doughnut binge he recently went on after he finished filming the highly anticipated Deadpool sequel.
There is a distant hint of a dad bod lurking under the 50-year-old's black T-shirt, but it's unconvincing. He is still in undeniably great shape.
And that is because Brolin is the unexpected action star of the moment. It will be close to impossible to walk into a cinema this summer and not see him on screen.
He plays the huge purple villain Thanos in the box office behemoth Avengers: Infinity War, as well as Cable in Deadpool 2, not to mention his return as federal agent Matt Graver in the Sicario sequel.
So who could have predicted that Brolin, best known for films like No Country For Old Men, Inherent Vice and Milk, would end up in two huge comic book movies in such quick succession?
"Nobody!" he laughs. "Especially my agent, who is very happy about it right now.
"They were completely different to anything I had done before.
"I have always mixed it up and whatever roles I've chosen have been different, but I think that these three coming together in one summer is crazy.
"And the fact they are different, even though two of them are tent-pole movies, I just think they are fun characters, man."
But joining two big franchises required a crash course in comic book vernacular.
"I do get all the references in Avengers now. I didn't see it until the premiere and I missed a lot because I didn't realise the things that happened were going to happen so I got uncomfortable in the theatre," he says.
"I didn't know how people were going to react after the movie was over.
"Then my wife and I went to another theatre, a small theatre, and we saw it again and you pick up a lot of things."
He looks bashful. "You don't want to say that you go to see your own film a lot because it sounds horrible but I'm actually excited about seeing it again."
His father, the actor James Brolin, who is now married to Barbra Streisand, has already caught a showing.
"I talked to him the next day and I said, 'What did you think?' and he said, 'I didn't get it', which I thought was pretty good.
"Keeps you humbled man. Keeps you down to the ground. Not under the ground, just right at ground level."
He was convinced to sign on for Deadpool 2 after an unexpected inspiration - seeing his co-star Ryan Reynolds in the 2009 romantic comedy The Proposal, in which he stars opposite Sandra Bullock.
"It was instrumental in me becoming an actor!" he jokes. "I kind of threw it away before that, but once I saw The Proposal I realised I need to get serious if I want to be the proper hunk, to be seen as a true teen idol. I love Ryan, I do. I love that movie, all joking aside.
"I make jokes about it but the truth of the matter is, I sit there and I have a tear fall down my cheek and there is total idolatry."
Reynolds, who reprises his role of the Merc With The Mouth for Deadpool 2 is one of his man crushes, it seems. Another is the action star behind Deadpool's rival, Wolverine.
"I know a lot about Hugh Jackman because I'm a big fan," he says with a twinkle in his eye. "I know that he lifts heavy weights in between movies, I watch a lot of those videos. Hugh Jackman is my secret little romance. Maybe I'm his, lets hope. Actually no, I'm too Neanderthal for him."
But Brolin himself is now no stranger to heavy weights. He got in what looks like the best shape of his life to played the ripped Cable in Deadpool 2.
"I did put in some work but Hugh Jackman always stays perfect like Ryan. I'm a guy that when the movie is over I just go right to the doughnut shop."
And so that brings us back to the lifting up of the shirt, to show off the effects of those doughnuts.
"It's not that I can go to the doughnut shop when it's over, it's that I can't help but run to the doughnut shop," he confesses.
"It was like I had smoked crack. I went for two doughnuts and then I left and I didn't even know that I had turned around, bought another three doughnuts, had those, then had two more doughnuts after that.
"Then I was going through the streets and I was freaking out from sugar so much that I for sure looked homeless.
"But it was still fun, I recommend it for anybody who has been off sugar for six months."
But the time will come when he has to get ripped all over again, when he reprises the role for the X-Force movie.
And this time, he will be aiming to get even buffer.
"I maintain right now. I don't really watch what I eat but I maintain and then when we get back into it, there is a whole new plan - we want to go a little bit bigger, it will be fun," he says.
"I've never done this kind of body sculpting before, as lame as it is to talk about and as embarrassed as I feel talking about it right now.
"I know it's good for you, it's fun doing it and I have a great trainer, Justin Lovato, but when you don't eat sugar and you have to weigh all your food and you have to be at the gym three hours a day, it's only fun for a little while."
Deadpool 2 is at UK cinemas now