Despite being canonically tied to HBO Max's "Harley Quinn", the role of Lex Luthor was recast to the now late Lance Reddick. He took over the role from Giancarlo Esposito (who voiced the character in the aforementioned "Harley Quinn") due to scheduling conflicts.
Dean Lorey left his showrunning position for Harley Quinn (2019-presnt) in favor of working on this spin-off.
Noonan's Bar actually exists in DC Comics.
Originally titled Noonan's.