There can have been few teachers happier with life than I was. I would read stories in The TES of widespread despair, stress and disenchantment with, I’ll confess, wistful self-satisfaction.

Then our head, a widely respected and much-loved figure, retired and a replacement was appointed. This man, whom I shall call Quasimodo, seemed okay, if a little bland, when we met him briefly at interview.

But one day during the term before he took up his post, someone from his school called our staffroom and asked to speak to the most senior member of staff present, who happened to be me. The caller, a woman, said we had made a terrible mistake in appointing Quasimodo, who was “an incompetent monster”. (In the two years that followed, that description remains the most charitable I heard.) She went into some detail about our new boss. He drank heavily at staff gatherings and then made “disgusting” remarks to and about female colleagues. He had casually suggested that heads of departments should “re-process” old coursework that had been posted back by the boards. He had arranged to have money allocated to his own projects, money which later disappeared.

She spoke in a breathless hurry. When I think of her call now I see it in cinematic terms: having to get the vital message out before a sinister figure appears at the door.

I thought at the time it might be a case of personal grievance boiling over in a melodramatic outburst. But no. Every one of her warnings (and there were others just as serious) proved to be justified. The man was a petulant tyrant. It got to the point where I couldn’t be in the same room as him without my jaw and fists clenching in suppressed fury.

His manner always reminded me of Squealer in Animal Farm, when “he cast a very ugly look at Boxer with his little twinkling eyes” after Boxer questioned the new official view of Snowball. If he felt any hint of disapproval or resentment from particular members of staff he would pile on extra work for them until they reached breaking point.

For me, the final straw came when he forced us to adopt an unnecessary and mind-numbingly intricate regime of assessment which took an age to administer and collate and which was all promptly put in a cupboard and forgotten. I left teaching soon afterwards. I am now building a new career.

We all know that terrible candidates are given glowing references by schools who just want rid of them. They then move on and do even more damage.

Here’s a possible solution. Let a delegated group of teachers visit the candidate’s school. Of course, they’d have to go disguised as window cleaners or photocopier repair men, otherwise they’d be treated to an Ofsted-style pantomime, with everyone gritting their teeth and saying nice things about the candidate. No one would be able to get near his office for droves of sweetly smiling teachers lining up to present him with tea and exotic chocolates.

There’s a good business opportunity for ex-teachers: “SchoolSnoops! Discretion guaranteed. We’ll get the dirt on your new boss, before he gets dumped on you!”

The writer wishes to remain anonymous