YOU tread a very dangerous path if you are a character actor all of a sudden playing it straight.

In Big School (Tuesdays, 8.30pm, WIN), we have not one, but two of the modern era's greatest in David Walliams and Catherine Tate.

I have long been a fan of both of these UK stars, but I love them because of - and indeed they are famous for - the brilliant array of super-quirky characters in their performance arsenal.

Seeing them play normal people is, well, abnormal.

I have watched the first few episodes of this new series with knee-jerk anticipation of a funny face or weird accent, but neither has been forthcoming (if you don't count occasional lines in semi-French, as Tate's character is a French teacher). Wacky make-up, a misplaced hair piece, fake nose or fat tummy? Nada. My kingdom for some buck teeth!

It's not that I'm shallow, I am just accustomed to a certain delivery of humour from these two and some big adjustment is needed when watching this show.

Set in Greybridge School, it's a comedy about high school teachers and their dysfunctional relationships. Chuckles are guaranteed as you recognise teachers from your own high school reflected in the caricatures up on screen: the leery PE teacher, the scary-mute lab assistant, the nervous-breakdown-near geography teacher and the music teacher with one exasperated eye on Broadway.

Frances De La Tour as pickled headmistress Ms Baron is hilarious and the plot action is realistic and interesting.

Just be warned, the leads are playing with a straighter bat than Tendulkar's.