Porridge: 70s 'Comedy Gay' Gold

I can't believe it's 40 years since the first episode. Even now I'm stopped in the street by people eager to talk about Porridge. It was great family entertainment and remains as popular as ever.

I was just 25 when I was invited to meet Syd Lotterby, the producer and director, at Television Centre to discuss a new sitcom. Being a young actor I was terribly starstruck and had no idea that the series had been written for my all-time favourite comedy actor Ronnie Barker, who was to play old lag Norman Stanley Fletcher. So when my agent told me I'd got the part of Lukewarm I was over the moon. I immediately rang my parents who were thrilled.

When Syd discussed the character he asked if I minded playing an "iron hoof" which is a wonderful rhyming slang term for "poof". I didn't mind at all but was determined not to make him outrageous. Back then it was still unusual for a gay character to appear in a sitcom.

I ended up playing him a bit like me. I used to like knitting so I suggested Lukewarm - who got his nickname from working in the prison kitchen and always preparing tepid food - should knit. The problem was he wasn't very good at it and never finished anything. The public loved it and I received letters from people asking what Lukewarm would be knitting in the next series.

In 2003 the BBC screened Life Beyond The Box, revealing how the inmates had fared 25 years after the show. My character was married to Trevor, his boyfriend in the original series, and had copious knitted sweaters and bobble hats around the house. It was so funny.

Christopher Biggins remembers his groundbreaking role in Porridge, 30 years on, in the Express.