Christy Carlson Romano as Kim Possible (voice)

Will Friedle as Ron Stoppable (voice)

Nancy Cartwright as Rufus (voice)

Tahj Mowry as Wade (voice)

Mayim Bialik as Justine Flanner (voice)

Gary Cole as Dr. Possible (voice)

John DiMaggio as Dr. Drakken (voice)

Shaun Fleming as Jim Possible / Tim Possible (voice)

Rob Paulsen as Hank Perkins (voice)

Brian George as Duff Killigan (voice)

Tom Kane as Monkey Fist (voice)

Kerri Kenney as Additional Voices (voice)

Melissa McCarthy as Amy Hall (voice)

Jean Smart as Dr. Ann Possible (voice)

Kirsten Storms as Bonnie Rockwaller (voice)

Nicole Sullivan as Shego (voice)

Raven-Symoné as Monique (voice)

Patrick Warburton as Steve Barkin (voice)

Gedde Watanabe as Professor Bob Chen (voice)

Jo Anne Worley as Additional Voices (voice)

Frank Welker as Professor Otto Allenford (voice)

Diedrich Bader as Lars (voice; uncredited)

Eddie Deezen as Ned (voice; uncredited)

Clyde Kusatsu as Nakasumi (voice; uncredited)

Maurice LaMarche as 'Big Daddy' Brotherson (voice; uncredited)

Phil LaMarr as Ninja / Japanese Businessman #2 (voice; uncredited)

Kevin Michael Richardson as Sumo Ninja / Dr. Gooberman / Businessman (voice; uncredited)

Stephen Root as Cowboy Gambler (voice; uncredited)

Rider Strong as Brick Flagg (voice; uncredited)

Tara Strong as Computer (voice; uncredited)

Lauren Tom as Yoshiko (voice; uncredited)

Ricky Ullman as Eric (voice; uncredited)

April Winchell as Reporter (voice; uncredited)