The Argus: Brighton Festival Fringe launches today

“The worst thing about being a teacher isn’t the students. It’s the other teachers.”

We’ve all been there – that moment when you’re about to leave a job, and that little voice at the back of your head says: ‘Tell them what you really think of them’.

In the case of departing humanities teacher Andy Thomas that little voice is comic Kenneth Williams – who guides Thomas through the troughs in his career using television, film and radio parodies.

Crimes Against Humanities Teachers has the ring of true-life experience to it – from the classroom accusations of homosexuality (for standing too close to another male teacher in assembly) to the lesson on Nazi propaganda that went too far.

Thomas’s opening anecdotes raise a few giggles as he practices his initial speech, in an outrageous costume that felt like a good idea in the pub.

The pace picks up when the ghost of Williams - a bravura performance by Colin Elmer - appears to recreate a series of the Carry On hero’s biggest moments: from Just A Minute to a brilliantly executed take on Will O' The Wisp.

A quickfire Mastermind section also works well, and the Jackanory history of chalk will resonate with anyone schooled pre-1985.

Once Williams’s back catalogue is exhausted the play loses steam – especially during an over-extended Katy Perry song and fairly obvious takes on EastEnders and Casualty.

Despite having won an award at the Fringe for best comedy show two years ago, this feels like a promising debut in need of some judicious editing to find its true potential.