Series regular Abel Fernandez is seventh-billed in the closing credits, but does not appear in the episode.
This is the fifth of eight appearances Grant Richards makes in the series. For most of these appearances, he takes on the persona of different characters. In three of his appearances, this not being one of them, he plays the hoodlum Frankie Resko.
Given an uncredited bit part as a prisoner in this show, Charlie Picerni is perhaps better known in the industry for his work as a stunt coordinator/director, as well as performing stunts and acting as stunt doubles for other actors. His work in Die Hard (1988) and the franchise that followed made him a star in the field of movie stunts. The actor who plays Lee Hobson in The Untouchables (1959) is in real life his brother.
Frank Nitti likens Nick Dolov to Barney Google, a comic strip character created by cartoonist Billy DeBeck and first published in newspapers in 1919. The character was a caricature of the dandy, wearing top hat, gloves, and tails, but with goggle-shaped eyes and light-bulb-shaped nose.