The B-movie dick, Michael Shayne:
Less noble than slick -- I'm just sayne.
Before he's begun
To figure who dun,
He's eager to pick out who's payne.
Donald B. Benson
In Dressed to Kill (Eugene J. Forde; 1941), detective Michael Shayne (Lloyd Nolan) stumbles across a murder and immediately sets about collecting multiple clients to pay him to solve it.