Cameron Monaghan

as Caius

as Cal Kestis (voice)

as Clyde

as Sergei (voice)

as Special Agent Finley Sterling

as Chris Decker

as Kamandi (voice)

as Ian Gallagher

as Jeremiah Valeska/The Joker (archive footage)

as Ferris Bueller

as Self

as Connor Kent / Superboy (voice)

as Self

as Connor Kent / Superboy (voice)

as Luke Hunter

as Ross

as Aaron

as James Walker

as Tom Fairfax

as Jerome Valeska

as Jeremiah Valeska

as Joker

as Asher

as Adam McCormick

as Jeff

as Mason Ashford

as Carlos

as Corey Doyle

as Corey

as Ian Gallagher

as Jack

as Cody Grice

as Jonathan McKenna

as Larry Parker

as Bob Andrews

as Young Boy 1

as Dexter

as Elliot

as Tyler Carson

as Bob Andrews

as Traffic Cop #1

as Kevin O'Doyle

as (archive footage)

as Jeffrey Charles

as Twin 1 (voice)

as Todd

as Timmy

as Palmer Noid

as Nick Peyton

as Winthrop Paroo

as Danny Cooper

as student (uncredited)

as Chad

as Eddie Sandow

as Eddie Sandow