The Venture Bros. cast is including:
Doc Hammer as Dr. Girlfriend / Henchman 21 (voice) (81 episodes), Christopher McCulloch as Hank Venture / The Monarch (voice) (81 episodes), Patrick Warburton as Brock Samson (voice) (81 episodes), James Urbaniak as Dr. Venture (voice) (81 episodes), Michael Sinterniklaas as Dean Venture (voice) (81 episodes), Steven Rattazzi as Dr. Orpheus (voice) (31 episodes), Lisa Hammer as Triana Orpheus (voice) (14 episodes), Paul Boocock as Dr. Jonas Venture (voice) (4 episodes), Brendon Small as Action Johnny (voice) (2 episodes), Dana Snyder as The Alchemist (voice) (2 episodes), Bill Hader as Professor Impossible / Alien villain (voice) (1 episode), Toby Huss as General Treister (voice) (2 episodes)