First broadcast 29th November 1968.

A violent pupil returns to the school.

John Alderton - Bernard Hedges
Deryck Guyler - Norman Potter
Noel Howlett - Mr. Cromwell
Joan Sanderson - Doris Ewell
Richard Davies - Mr. Price
Erik Chitty - Mr. Smith
Liz Gebhardt - Maureen Bullock
Penny Spencer - Sharon Eversleigh
Peter Cleall - Eric Duffy
Malcolm McFee - Peter Craven
Peter Denyer - Dennis Dunstable
David Barry - Frankie Abbott
Ann Lancaster - Mrs. Pearce
Winifred Braemar - Mrs. Armitage
Fred Beauman - Uncle Niklos (as Frederick Beauman)
Roger Carey - Abapellogopholis
Alan Mason - Fireman
Tony Alleff - Niklos' Sidekick (as Tony Allef)
Alister Williamson - Mr. Duffy
George Georghiou - Pupil in checked shirt