Green’s Dictionary of Slang

information; the proper way of doing things, the recognized procedure; esp. in phrs. what’s the drill? how are things done (round here)?; know the drill, to understand the way things are done.

1960		Wodehouse Jeeves in the Offing 28: What’s the drill? Do I kiss you a good deal from time to time?
1972		J. Mills Report to the Commissioner 63: He’d been mugged so often he knew the drill.
1976		D. Ireland Glass Canoe (1982) 57: The drill is, I stop and you get out. Go up to the official party and shake their hands and I’ll wait here.
1997		Mad mag. Jan. 36: You know the drill. I come out under-dressed and frequently unshaven to the audience’s immediate Pavlovian reaction.
2001		J. Stahl Plainclothes Naked (2002) 247: You’re under arrest. You know the drill, right?
2002		S. Maloney Something Fishy (2006) 33: So what’s the drill [...] You arrest them, or what?
2008		R. Price Lush Life 42: Talk to the porters, the token clerk, you know the drill .
2010		L. Redhead Thrill City [ebook] I knew the drill so I pressed the buzzer.
2011		‘Jack Tunney’ Split Decision [ebook] She knew the drill. I’d meet her out front. She couldn’t make it to the locker rooms.
2014		T. Black Artefacts of the Dead [ebook] Check it out [...] you know the drill.
2016		D. Whish-Wilson Old Scores [ebook] Candice was a big unit, and she didn’t flinch. Swann still looked cop, and she knew the drill.
2023		(con. 1962) J. Ellroy Enchanters 351: Paul de River. Give us the drill of that quack.