The vintage year of the wine Bruce brings up from the cellar is 1966: the year that Batman (1966) premiered.
Jeffrey Combs, who plays the office manager that tries to negotiate with Fish Mooney, also plays the scarecrow in Batman: the Animated Series.
Although only Gus Floyd (Michael Goldsmith) and Clyde Destro (Jonny Coyne)'s names are mentioned, the other members of the Red Hood Gang are Jack Regan (Kevin T. Collins), Baz Haskins (Peter Albrink), and Beck Trope (Peter Brensinger).
In the scene where Oswald and Butch are sharing drinks, a 1950s style "Penguin Ice Bucket" can be seen on the bar between them.
Trope (Peter Brensinger) did not have a stutter in the original script, but was given one at director Nathan Hope's suggestion.