He’s been on screen since he was seven – but only prepares for a scene 10 minutes before. Yet somehow the mischievous Succession star is now tipped for an Oscar. How did the chaotic, charismatic actor do it?

Kieran Culkin tries the upright chair first, the one opposite me, high-backed and leather. But no, that’s no good. He can see his reflection in the wall mirror, he’ll be catching himself all interview, thinking how tired he looks with his hooded eyes and beard, how jet lagged. Sleep is always tricky, but he’s been up with the kids – five and three – who weren’t supposed to join him for this publicity tour but there was a last-minute crisis, the short version of which is that the whole family is over from New York (with Culkin, 42, there’s always a long and short version).

So, he flumps on the banquette, where he’ll be facing guests drinking afternoon cocktails in the low-lit, high-ceilinged bar here at the Corinthia hotel in London. He tests the firmness of the upholstery. Pantomimes boneless relaxation. Looks at me to gauge the distance between us. No, this won’t do, either. He’s too low, these people are distracting and, proximity-wise, he’s a little close. He scrambles back to the chair. Grabs the drinks menu. Muses that you may as well have the expensive thing if you’re not paying, orders champagne plus whatever trimmings, strains to peek at my notes. “Your fun notes. Notes I am not allowed to see.” He taps his phone screen, “OK, your time starts … now.” Cackles like a cartoon villain. “Yeah, just kidding.”