Doc Hammer (37)

Dr. Girlfriend / Henchman 21 (voice)

Christopher McCulloch (32)

Hank Venture / The Monarch (voice)

Patrick Warburton (39)

Brock Samson (voice)

James Urbaniak (40)

Dr. Venture (voice)

Michael Sinterniklaas (31)

Dean Venture (voice)

Misha Collins (29)

Prisoner 2 / Maestro Wave (voice)

Patton Oswalt (35)

Wonderboy (voice)

H. Jon Benjamin (38)

The Master (voice)

Nathan Fillion (33)

Brown Widow (voice)

Stephen Colbert (40)

Professor Impossible (voice)

Seth Green (30)

Lance Hale / Mrs. Z (voice)

Steve Park (42)

Mike Sorayama (voice)

Gillian Jacobs (21)

Marsha Backwood (voice)

Kevin Conroy (48)

Captain Sunshine (voice)

Charles Parnell (39)

Jefferson Twilight (voice) / Mandalay (voice) / Mister 1 (voice)

Lisa Hammer (37)

Triana Orpheus (voice) / Jeanie / Leslie Cohen / Lesliebots (voice) / Princess Tinglepants (voice) / Jeanie (Mrs. Tom) (voice)

Brendon Small (29)

Action Johnny (voice) / Swifty / Hector / Crime-o-dile Henchman / White Noise (voice) / Jonny Quest (voice) / Resistance 1 (voice) / Sgt. Hatred (voice) / Dr. Vulcano / Master Yourname (voice) / Action Johnny / Blind Rage (voice) / Surgeon / OSI Scientist / SPHINX Agent 1 (voice) / Agent Hauser (voice) / Plastic Surgeon (voice) / Hector / Swifty / Whale Lice Henchman 1 (voice)

Terrence Fleming

Col. Bud Manstrong (voice)

Miguel Martinez-Joffre

Mexican Gangster / Mexican Student (voice)

Paul Boocock

Dr. Jonas Venture (voice) / Jonas Venture Sr. (voice) / Dr. Jonas Venture / Additional Voices (voice) / Priest 1 / Jonas Venture (voice) / Jonas Venture Sr. / Laugh Riot (voice) / Sonny / Interpreter / Little Jorgé (voice) / Tigerriffic / Therapist / Prison Guard 2 (voice) / Jonas Venture Sr. / University President / Homeless Vet (voice) / Dr. Jonas Venture / More Pirates (voice) / Jonas Venture Sr. / Psychiatrist (voice) / Dr. Jonas Venture / OCLF Leader (voice) / Highway Cop / Scared Straight Kid 1 (voice) / Sonnystein / Gill-Man (voice) / Fighter Pilot / O.S.I. Instructor (voice) / Jonas Venture Sr. / Sandow / Samuel Clemens (voice) / Sandow (voice) / Jonas Venture Sr. / Security Guard 2 (voice) / Jonas Venture Sr. / Additional Voices (voice)

Richard Liebmann-Smith

Preist 2 (voice) / Mexican University Administrator (voice)

Rachel Simon

Fantasy Mom (voice)

Tom Vollette

Singer (voice)

T. Ryder Smith (46)

Baron Ünderbheit (voice) / Baron Ünderbheit / Dean Harris / Otto Aquarius (voice) / Baron Ünderbheit / Otto Aquarius (voice) / Baron Ünderbheit / Soldier 1 (voice)

Bill Hader (26)

Flying Squid (voice) / Phineas Phage / Headshot / Flying Squid (voice) / Headshot (voice) / Professor Impossible / Phage (voice) / Professor Impossible / Alien Villain (voice) / Professor Impossible (voice)

Steffen Vala

College Student (voice)

Nina Hellman

J.J.'s Ride to the Marina (voice) / Kim (voice) / Lt. Anna Baldavitch / Woman on Cell Phone (voice) / Tijuana Prostitute (voice) / Kim / Jollyrancher82 (voice) / Lt. Anna Baldavich / Cassie (voice) / Prostitute (voice) / Woman in Court (voice) / Dr. Tara Quymn / Mz. Quymn / Nancy Quymn (voice)

Dana Snyder (30)

The Alchemist (voice) / President Breyer (voice) / The Alchemist / Mister Sample (voice) / The Alchemist / Parade Announcer 2 (voice) / Dog-Man (voice) / The Alchemist / Bonibozo Tribesmen (voice)

Cristin Milioti (18)

Sirena (voice) / Sirena / Nurse (voice) / Sirena / Millinery Ghosts (voice) / Novia / Receptionist (voice) / Sirena / Mrs. Wandering Spider (voice) / Stab Girl / Mrs. Fitzcarraldo (voice) / Sirena / Madison (voice) / Night Nurse Cindy Marie Abrams (voice) / Kate (voice)

Mia Barron

Molotov Cocktease (voice) / Sally Impossible (voice) / Girl Hitler (voice) / Sally Impossible / Jonas Jr.'s Ibezan Houseguest (voice) / Molotov Cocktease / Debbie (voice) / Ladyhawk Johnson (voice) / Molotov Cocktease / Island Girl (voice)