If someone asked you what connected comedian David Walliams, The Who frontman Roger Daltrey and Hollywood star Keira Knightley, could you tell them?

It may surprise you to know that at one time or another, they have all starred in The Bill.

The chances are, unless you’re an ardent fan, you won’t have realised just how many of our nation’s biggest stars have walked through the doors of Sun Hill police station.

Former EastEnders actor Martin Kemp presents as the show takes a look back over the history of the long-running show.

He also reveals just how much of an impact it has had on the careers of a number of well-known celebrities.

Now 25 years old and still going strong, The Bill is one of the longest-running crime dramas in the world, and follows the lives of officers at Sun Hill police station in the fictional east London district of Canley.

Starting out in 1983 as a pilot for Storyboard named Woodentop, it followed the first day on the job of rookie PC Jim Carver, who, played by Mark Wingett, would go on to stay with the show for more than two decades and become one of its most popular characters.

Going from strength to strength over the years, the show’s success is mirrored by the calibre of the guest actors it has featured.

Commemorating the show’s 25th anniversary, this special documentary features exclusive interviews with stars past and present, who reflect on how the show has developed over time, and discuss what impact their involvement with the series had on their careers.

Michelle Collins is no stranger to soapland, having portrayed Cindy Beale in EastEnders on and off for 10 years, as well as taking leading roles in dramas Sunburn and Two Thousand Acres of Sky.

However, it was The Bill that gave her an early break. As she explains: “Like it is now, it was really respected, so to get a good, gutsy part in The Bill was quite a coup. It definitely helped my career.”

Another entertainer whose CV received a shot of adrenaline from an appearance on the show was Paul O’Grady, who, then known as Paul Savage, did a three-episode stint as a transvestite named Roxanne in 1988.

”It was my first telly job,” he reveals. “I was working at the Vauxhall Tavern and one of the casting directors came down and said ‘do you fancy being in The Bill?’ ”They had a lot of trust in me and I was really grateful for that. At the time I thought I was the new Garbo. I’ve got such happy memories of it, I’d like to go back and play a villain. A really twisted serial killer.”

Whether villain, victim or cop, there have been all kinds of people appearing In The Bill over the years, and fans will be pleased to know that Roberta Taylor, Darren Day, Les Dennis, Pauline Quirke, Ben Richards and Todd Carty are among those famous faces who will be discussing their experiences on the show.