Milo (performance capture)

Seth Green

Acting

Milo (voice) (as Seth Dusky)

Seth Robert Dusky

Acting

Mom (voice)

Joan Cusack

Acting

Gribble (voice)

Dan Fogler

Acting

Alien (voice)

Breckin Meyer

Acting

Ki (voice)

Elisabeth Harnois

Acting

Milo's Dad (voice)

Tom Everett Scott

Acting

Supervisor (voice)

Mindy Sterling

Acting

Martian (voice)

Julene Renee

Acting

Martian Hatchling (voice)

Raymond Ochoa

Acting

Martian Hatchling (voice)

Robert Ochoa

Acting

Martian Hatchling (voice)

Ryan Ochoa

Acting

Martian

Amber Gainey Meade

Acting

Two-Cat (uncredited)

Dee Bradley Baker

Acting

Martian

Adam Jennings

Acting

Martian

Aaron Rapke

Writing

Martian

Jacquie Barnbrook

Acting

Wingnut

Kevin Cahoon

Acting

Martian

Kirsten Severson

Acting

Martian

Matthew Henerson

Acting

Martian

Stephen Kearin

Acting