We’re The Sweeney, son, and we haven’t had any dinner.’ Mention the phrase in Britain now and some people — not all just men of a certain age — will immediately know you’re talking about the dynamic 1970s’ cops and robbers show.

John Thaw, playing Jack Regan and a young Dennis Waterman as George Carter.

“I played a tough guy called Skef Warren, who was the minder, in a Sweeney episode called Stay Lucky Eh?,” recalled John Challis, who will be talking about his fascinating acting career in Only Fools and Boycie at the Thwaites Empire Theatre, Blackburn, next Thursday.

“They said I was so hard they could have skated on my face,” he joked. “But the truth was I’d never hit anybody in my life.

“I was as soft as putty. The producer got this big gripper in to teach me how to fight.

“The shoot-out scene was at Wimbledon Theatre, and when Frank Haskins and Jack Regan pumped a few bullets into me, that was the end of my Sweeney career.

“It was great fun to do and John Thaw was such a funny man.

“He was a giggler and loved life. We spent half the time laughing and joking but as soon as the camera was switched on, he was the ultimate professional and a wonderful actor.

“I learned so much of my craft doing television work like that.”

A prolific character actor, Challis starred in TV shows including Citizen Smith, Coronation Street, The Bill, Heartbeat and Dr Who. But it wasn’t until he landed the role of Boycie, a wide boy second-hand car dealer in Only Fools and Horses that he became a household name. A spin-off series The Green Green Grass followed.

“Doctor Who was madness but I loved the part,” added Challis.

“I was Scorby in the Seeds of Doom, the henchman to a mad scientist, who discovers a pod of aliens buried in a mountain of 20,000 year old permafrost.

“I got captured by the Krynoids, though, and that was the end of me.”

Even the curse of the terrifying Krynoids pales into insignificance when Challis rolls back the decades to a never-to-be forgotten evening with wild man Oliver Reed.

“The first film I had a part in was the New Spartans, about a group of mercenaries with Reed as the star.

“Reed was such a charismatic man, but his behaviour was extraordinary.

“We went to the hotel lounge on the first night and there was Ollie, having a mock Kung-Fu battle with two Chinese extras.

“They destroyed the room and the bill was paid for out of the film’s budget, and needless to say it didn’t get released.”

Only Fools and Horses attracted audiences of 25 million at its peak and after seven series the cast were all national treasures.

Boycie’s best pal was dopey road sweeper Trigger, played by Roger Lloyd-Pack who died in January.

The two actors had been close friends for three decades.

Challis added: “It was a terrible shock. It shook me.

“Roger always kept his cards close to his chest. He didn’t want anyone to know he was ill.

“He was a very serious actor. He loved poetry, and the last thing I saw him in was a Shakespeare play at the Globe Theatre.

“In times like this I do think of Only Fools and it makes me smile again.

“We all had a wonderful time together and I’ll treasure them.”

An evening with John Challis, who will also be signing copies of his autobiography, Being Boycie, Thwaites Empire Theatre, Ewood, Thursday, March 27. Details from 01254 685500.