| Harry Hill |
Professor Branestawm |
| Madeline Holliday |
Connie |
| Simon Day |
Colonel Dedshott |
| Vicki Pepperdine |
Mrs. Flittersnoop |
| Sophie Thompson |
Aggie |
| David Mitchell |
Harold Haggerstone |
| Adrian Scarborough |
The Vicar |
| Charlie Higson |
The Mayor |
| Jason Forbes |
P.C. Peasey |
| Doreen Ingleton |
Miss Silt |
| Ben Miller |
Mr. Bullimore (Series 1) |
| Miranda Richardson |
Miss Blitherington (Series 1) |
| Barbara Durkin |
Angelica (Series 1) |
| Jason Maverick |
Robo Dad (Series 1) |
| Nathaniel Gleed |
Teenage Branestawm (Series 1) |
| Isaac Stanmore |
Young Bullimore (Series 1) |
| Lily Travers |
Young Miss Blitherington (Series 1) |
| Diana Rigg |
Lady Pagwell (Series 2) |
| Steve Pemberton |
Professor Algebrain (Series 2) |
| Maya Sondhi |
Radio Producer (Series 2) |
| Rosie Cavaliero |
Mary Oxford (Series 2) |
| Matt Berry |
Professor Awfulshirt (Series 2) |
| Justin Edwards |
Radio Announcer (Series 2) |
| Alexa Morden |
Miss Pagwell (Series 2) |
| Lily Palmer (as Lily May Palmer) |
Maisie (Series 2) |