With his parents on a getaway, Horrid Henry is chosen for the Brainbox of the Year contest and faces off against his nemesis alongside a quirky team.
| Actor | Role |
|---|---|
| LLizzie WaterworthNot listed | Not listed |
 Aidan CookNot listed | Not listed |
 Wayne ForesterNot listed | Not listed |
| TTamsin HeatleyNot listed | Not listed |
 Sue Elliott-NicholsNot listed | Not listed |
| JJoanna RuizNot listed | Not listed |
 Emma TateNot listed | Not listed |