First broadcast in 1971/2 'Please Sir!: The Complete Fourth Series' was a huge hit for ITV, and was written by John Esmonde and Bob Larbey - the team that would go on to create 'Ever Decreasing Circles' and 'The Good Life'. It's all change at Fenn Street this term - the old class 5C have now moved on (see their adventures in the Fenn Street Gang) and a new class of youngsters has started. Bernard Hedges feels that it's time to leave also and is soon replaced by the effete David Ffitchet-Brown and the mad bully Gregory Dix. As the new intake of pupils try to survive school life, Potter finally gets what he's always wanted - an assistant - but headmaster Cromwell makes the big mistake of trying to enforce a dress code at school and it blow up in his face!