Five shots, preferably but not necessarily, of the cheapest
hard-liquor in the bar. The shots are lined up in a row and consumed, one after the other, in rapid succession. It is often used by people who, having arrived at the bar or club late in the
evening, need to catch up in order to have a good
time.
Mike: "Shit, I'm late and all you fuckers started drinking without me."
Tom: "No problem
bro, just do The London Classic and you'll be good to go."
Mike: "Fuck, I knew you were going to suggest that." *Facepalm