Possibly the nation's favourite (and tightest) second-hand car dealer, Only Fools and Horses' Boycie is a classic among comedy characters.
Challis confesses his heart is in the theatre and he's appeared with Sue Holderness in a series of Alan Ayckbourn plays. His TV career boasts performances in The Sweeney, Citizen Smith, Heartbeat and Soldier Soldier to name a few. Home to John and his wife Carol is a 12th century, eight-bedroom pile in Wigmore Abbey which they're renovating. Here's what he has to say...
What's your all-time favourite TV programme?
Only Fools and Horses of course! It's the best there is!
If you weren't doing this job what would you be doing?
I love gardening so I'd either be a gardener or a forester. We have five acres of land at our home in Shropshire, one acre of which is garden. It's got fruit trees, flowers and plants. I love it.
If you could take your pick of one leading role which would it be?
Ever since I saw Christopher Lee and Peter Cushing in the Sixties I've longed to be Count Dracula. I was terrified.
Have you ever turned down a role you later regretted?
Tell us about your most memorable filming disaster.
It was back when I was a fairly inexperienced actor. I was working on set as a young revolutionary leading a band of brothers. I'd eventually managed to organise this bunch of hooligans and we shot the scene, only to realise that the director had fallen asleep!
What was the last film you went to see at the cinema?
War of the Worlds. It was OK, a bit formulaic to be honest. Tom Cruise was good and the special effects were too, but I wasn't bowled over by it.
If you were controller of a TV channel for the day, what would your schedule look like?
I'd call it BBC No Choice and it would feature Only Fools and Horses 24/7!
What's your idea of a perfect Sunday?
We'd get up late, buy the papers and sit round the kitchen table reading them. Then we'd go for a long lunch with dear chums and walk home, take a nice siesta and watch CSI in the evening. I like the women - they're impossibly glamorous!
Talk us through a day in the life of John Challis
I don't have much of a routine. We tend to be quite instinctive. At the moment we're on top of a mountain in Shropshire.
What advice have you got for aspiring young actors?
Don't be put off. If you really want to do it keep on. You have to have staying power and you also need thick skin. So what if you have a couple of false starts, the important thing is having a go.