OK, so tell me, why do they all love Sir?

Actually they don’t, not at first. In the early days of Swinging London Mark Thackeray takes a job at North Quay secondary school because there’s no work for West Indian engineers down the East End, even if they do look like Sydney Poitier. Naturally he’s assigned the worst class in the school.

And turns them on to education and self betterment?

No. Quite the opposite. They decide to destroy him.

So it’s Blackboard Jungle all over again, only this time Syd’s the teacher not a pupil.

Does seem to be going that way at first. On arrival, poor Thackeray makes a fundamental mistake (he assumes his students want to learn). In fact most of the toughs in 5C just want to fight each other or listen to rock and roll while Judy Geeson has her mind set on seducing Sir and - worst of all - Lulu wants to sing.

It makes him want to shout. (Younger readers who never heard the Lulu “hit” that this line refers to can count themselves lucky.) Fortunately, Lulu (aka Babs Peggs) isn’t too prominent in the film. The big question comes down to whether it’s chief headbangers Denham or Judy G who land a smacker on Thackeray first.

I know which clinch I’d go for (were it not wholly unprofessional of course).

Sensibly Thackeray avoids what Chris Woodhead called an “educative experience” and dons boxing gloves instead. He throws out the textbooks and declares that from now on he’s going to teach 5C “survival skills” - real-life instruction based on the notion that if they want others to respect them they’ve got to start respecting themselves first.

Was that on the national curriculum in those days?

Sure wasn’t, which means that Thackeray’s staffroom colleagues go through all the standard routines of apoplexy and disbelief. Look out for Suzy Kendall, Rita Webb and Patricia Routledge as “Clinty”, none of whom reckons that the suddenly popular Mr Thackeray will last.

And does he?

Well, true to form, just as Thackeray is really beginning to transform the whole East End of London, the offer of an engineering job comes through. This means that Syd can escape from a bunch of no-hopers destined to spend their declining years propping up the bar at the Old Vic shouting “Tiffaneee!”. Better still he’ll be able to earn a decent wage and never have to listen to Lulu’s singing again.

So what does Thackeray do?

What do you think?

Adrian Mourby