Stephen Root Grampa (voice)
Ricky Gervais Flippy (voice)
Isla Fisher Sarah Hatoff (voice)
Pete Davidson Petey the Cat (voice)
Billy Boyd Seamus (voice)
Lil Rel Howery Chief (voice)
Maggie Wheeler Nurse (voice)
Kate Micucci Dippy (voice)
Cheri Oteri Mayor (voice)
Cam Clarke Indifferent Shop (voice)
Scott Menville 3D Guy (voice)
Poppy Liu Butler (voice)
Gary Rizzo Sound Re-Recording Mixer
Kelly Stables Harold (voice)
Laraine Newman Scientist (voice)
Luenell Milly (voice)
Christi Soper Hilt Casting
John Eric Bentley Living Spray Factory (voice)
Peter Hastings Writer, Dog Man / Officer Knight / Harold's House (voice), Director
Gary A. Hecker Foley Supervisor
Tom Howe Original Music Composer
Melissa Villaseñor Realtor (voice)
Kimberly Bailey Gym (voice)
Kevin McCann Grump (voice)
Max Koch Rocco (voice)
Skip Stellrecht Ice Cream Building (voice)
Brian Hopkins Editor, Big Jim (voice)
Hanna Kim Storyboard Artist
Adam Rosette Storyboard Artist
Carder Scholin Storyboard Artist
Warren Sroka Apartment Building (voice)
Jeff Gross Foley Mixer
Jeremy Bernstein Storyboard Artist
Mike Horton Foley Artist
Karen Foster Robot (voice), Producer
Dav Pilkey Book, Executive Producer
Rahnuma Panthaky Doctor (voice)
Nate Wragg Production Design
Shabrayia Cleaver Associate Producer
Georgia Simon Hospital (voice)
Tim Gibson Animation Supervisor
Daniel Tal Additional Storyboarding
Jana Schmieding Janet (voice)
Anthony Zierhut Head of Story
Pearce Bunting Cheesesteak Guy (voice)
Marceline Tanguay Storyboard Artist
Arran Jay Baker Lead Animator
Sarah Gold Amburgey Storyboard Artist
Aziz Kocanaogullari Lead Animator
Cassandra Fanning Digital Supervisor
Chris Heltzel Storyboard Artist
Gaël Matchabelli Lead Animator
Andrea Ferrara Lead Animator
Yung Gravy Mr. Whiskers (voice), Songs
Lucas Hopkins Calderon Li'l Petey (voice)
Percy Rustomji Surfer (voice)
Valentin Beaumont Visual Effects Technical Director
Christopher Zibach Art Direction
Scott Cullen Head of Layout
Bianca Margiotta Associate Producer
Sonny Onorati Radio Building (voice)
Emma Porter Lead Animator
Daria Khil Additional Storyboarding
Camryn Del Vecchio Additional Storyboarding