Dennis Waterman has teased his New Tricks swansong will feature some surprises.

The 67-year-old actor, who plays Gerry Standing – now the only remaining member of the original Unsolved Crime and Open Case Squad (UCOS), will bow out from the BBC One crime drama with a two-part episode, opening the show’s 12th series.

Dennis Waterman in New Tricks
Dennis Waterman in New Tricks (Amanda Searle/BBC)

“I can’t say too much but it’s a high action double episode with a big twist at the end so I think the fans are going to be happy. It’s the ending Gerry deserves,” he teased.

“I don’t think we find out any great revelations about Gerry but there are some surprises about his past that I think the fans will find interesting.”

The episodes, which begin tonight (August 4), have been written and directed by Julian Simpson.

“He’s a wonderful director so before the scripts even arrived, I was very confident that these final two episodes would be handled beautifully,” Dennis said.

“My favourite episodes were those written by Julian Simpson. Amanda Redman got him on board originally – he knew exactly what he wanted his episodes to look like and he had a gift for well-crafted, well-researched stories so I’m glad he was on board for Gerry’s final two episodes.”

His co-star Tamzin Outhwaite hinted Dennis will have an exit to remember.

“It was wonderful working with Dennis – he is such a legend, both on and off set. Dennis was the last remaining original cast member so it definitely felt like the end of an era and it was difficult to see him go,” she said.

“I think his final two episodes are fantastic though. When we heard that Julian Simpson was going to be writing and directing Gerry’s double-bill exit episode, we knew that he would give him a fitting farewell and I hope the fans enjoy it as much as we did.”

Dennis Waterman with Nicholas Lyndhurst and Tamzin Outhwaite
Dennis Waterman with Nicholas Lyndhurst and Tamzin Outhwaite (Amanda Searle/BBC)

Dennis, who has portrayed Gerry for 12 years since 2003, said his highlights from his New Tricks career were with the original cast such as Alun Armstrong (Brian Lane).

“A lot of my favourite moments were back in the day with the original cast – Alun Armstrong could have the whole crew on the floor with laughter, just making a cup of coffee,” he recalled.

“We took mickey out of each other – there were no barriers, no egos like you get on some shows and it was a classic ensemble of a group of people, all having a good time and being on camera doing it.”

Larry Lamb joins the 12th and final series of New Tricks, alongside Tamzin, Denis Lawson and Nicholas Lyndhurst.

Larry Lamb with his New Tricks co-stars - Denis Lawson, Tamzin Outhwaite and Nicholas Lyndhurst
Larry Lamb joins New Tricks, alongside Denis Lawson, Tamzin Outhwaite and Nicholas Lyndhurst (BBC/Headstrong Pictures/Amanda Searle)

Dennis said he will always have a soft spot for the show.

“I’d just like to say a big thank you (to the fans) for the support – we have fantastic viewers. We knew that the pilot was good, the cast was good and it just took off from there but no one could be prepared for the number of people who watched it. It’s been unbelievable,” he said.

“One lovely lady knitted scarves for all of us in winter – Alun still wears his in the summer!”

The new series of New Tricks begins at 9pm on BBC One tonight.