Greg Heffley is a scrawny but ambitious kid with an active imagination and big plans to be rich and famous – he just has to survive middle school first.
- Greg Heffley (voice): Brady Noon
- Rowley Jefferson (voice): Ethan William Childress
- Rodrick Heffley (voice): Hunter Dillon
- Susan Heffley (voice): Erica Cerra
- Frank Heffley (voice): Chris Diamantopoulos
- Manny (voice): Gracen Newton
- Fregley (voice): Christian Convery
- Braces Girl (voice): Jessica Mikayla Adams
- Teen Driver (voice): Cyrus Arnold
- Teen with Mullet (voice): Braxton Baker
- Homeroom Teacher (voice): Lossen Chambers
- Mrs. Fregley (voice): Brenda Crichlow
- Curly-Haired Girl (voice): Tessa Espinola
- Charles Davies (voice): Yuvraj Singh
- Mr. Underwood (voice): Billy Lopez
- Mr. Humphreys (voice): Donny Lucas
- Chirag Gupta (voice): Veda Maharaj
- Holly Hill’s friend (voice): Jaime Maclean
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- Producer: Brad Simpson
- Original Music Composer: John Paesano
- Producer: Nina Jacobson
- Director: Swinton O. Scott III
- Editor: Sylvain Blais
- Sound Re-Recording Mixer: Michael Huang
- Character Designer: Jeff Kinney
- Sound Re-Recording Mixer: Kenneth L. Johnson
- Casting: Micah Dahlberg
- Sound Designer: Sean Evans
- Animation Supervisor: Trent Noble
Credits: TheMovieDb.