- Headmaster (Felix Armstrong) – Headmaster
- Hector – English and General Studies teacher
- Irwin – History teacher; brought in as a special coach
- Mrs Dorothy Lintott – History teacher
- Akthar – Pupil; of Asian ancestry, Muslim
- Crowther – Pupil; acts as a hobby
- Dakin – Pupil; handsome, object of Posner's and Irwin's affection
- Lockwood – Pupil; strong opinions
- Posner – Pupil; youngest, gay and Jewish
- Rudge – Pupil; better known for athletic skills than for intelligence
- Scripps – Pupil; Anglican, plays piano
- Timms – Pupil; joker, overweight
- Director on Irwin's television programme (a small role)
Irwin is said to be modelled after Niall Ferguson.[3]
The play includes several non-speaking roles:
- Make-Up Woman, Production team – on Irwin's television show
- Three or four unidentified MPs – spoken to by Irwin in opening scene
- Other male pupils
- Fiona – Headmaster's secretary; object of Dakin's affection. Does not appear on stage in the published text, but was seen in filmed projections featuring Rio by Duran Duran during the original production.
