Smash hit

“Did you notice I got a black leather coat, though?” Simm says, proudly. “Black. It’s the only non-brown thing in the first episode.”

However brown and dreadful Life on Mars’s 1973 may be, it does bring home to you one thing: the 1970s were the best time to be a cop. I mean, the best. Hitting people, smoking fags in pubs, driving cars through walls of cardboard boxes, throwing evidence in bins, slapping women’s arses, and having a bravura attitude to punching a colleague (“I couldn’t give a tart’s furry cup if half your brains are falling out. It’s dinner time, and I’ m ’aving ’oops.”). You wonder why they bother making dramas about modern policing. In modern police dramas, the best thing that happens all episode is that someone in forensics finds an important fibre.

“But it was like that, wasn’t it?” Simm yelps. “You only have to look at all the dodgy cases from the 1970s and 1980s — the Birmingham Six, the Guildford Four, the Maguire Six — to know that it actually was all like that. They would just punch a witness, or lock a stroppy woman in a cupboard, or not bother to interview someone because they drank in the same pub and ‘he’s sound’. That’s why playing Sam is quite satisfying — as a man of the future, he teaches them a little bit about psychology, and paperwork, and not punching each other in the head all the time.”

Having reached our seventh round — “Whiskies!” — without having ordered those stomach-lining crisps, the talk turns to Britpop. Like most of our generation who now have partially ruined their lives with small children, Simm regards the Britpop era as a time of unending sunshine, excitement and beers. During Britpop, of course, Simm had two careers going: one as John Simm, actor, and the other as the guitarist in the psychedelic pop band Magic Alex. Although he’ s now settled on acting — perhaps because you really should concentrate on acting if you are the best actor of your generation — rock’n’roll is still where his heart’s at.

All night, no anecdotes fire him up as much as the ones about meeting Ian McCulloch from Echo & the Bunnymen (“I was just standing in line to shake his hand like a fan, and McCulloch shouted, ‘Lorraine! Lorraine! ’s then wife! It’s that kid from The Lakes!’ ”) or Oasis at Knebworth (“Helicopters with spotlights lit up Noel’s guitar, resting on an amp. I thought, before they even come on stage, this is the best gig ever”). Perhaps this explains how Simm does the thing that he does. After all, the best pop has a line of darkness through it — while the best rock’n’roll always takes you with it.

The next morning, I see Simm at the school gates — looking, it has to be said, quite wrecked. “I got so excited talking about music last night,” he says, “that I went home, drank a bottle of red wine and listened to Johnny Thunders until 5am.”

And then he explains how he can’t go to Clown Town that week.

Life on Mars, Mon, BBC One, 9pm

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