I'm moving at a dead run, breathing in tight bursts, the few pedestrians who are still around at this hour glancing back apprehensively as I approach them.
I'm in no particular hurry. But in a misguided way I have something to prove.
Mark Thomas laid down a devastatingly funny set that was more re-enactment than standup. He's met every kind of cop there is, bested most of them and befriended the rest. More than just angry, this man is angry and effective.
But ultimately this is politics, not comedy.
Nowhere is that clearer than after the show. I hang around to pick up his book, and while I'm at it I drop a pound in the jar for a tiny broken-kalashnikov badge. I like to keep a badge or two on my backpack when I travel, because occasionally people still pick my accent as American.
I'm buzzed from the show and the half-time beer, but the woman behind the desk looks deadly serious. Mark's mentioned a few of his, well, "co-workers" in his routine, and her eyes tell me that she's one of them. I gesture at their other line of badges, the ones that say "THIS IS AN ILLEGAL PROTEST".
"That's pretty cool. But I'm not heavily into getting arrested right now."
I'm trying to make light of a situation that isn't funny at all. She calls me on it, deadpan.
"Why not. I've worn these in Parliament Square."
All I can give her is the ugly truth.
"To be honest, I wish I had your courage. I'm doing a lot of travelling right now, and the last thing I need is more attention at the airport than I get already."
It's not, not really, but she doesn't labour the point.
I'll do that myself.
A hard mile later I'm slumped in a seat on the Northern Line with a book on arms dealing and a badge that doesn't say much at all. The copies of the Daily Mail left behind by the commuters have ten solid pages on Blair's departure, and I'm having a lot of trouble advancing my interior dialogue from "Send him to the Hague!" to how we'd actually get him there. Between stories I glance out of the window to read the name of the station we're passing through. Camden Town. I've been sitting for a long time.
Sooner or later I'm going to have to stand up.