THERE is a real air of poignancy about the arrival of Sherlock Holmes & The Ripper Mysteries at Darlington Civic Theatre next week. The play is from the prolific pen of Brian Clemens, creator of TV's The Avengers, and stars his son Samuel as the famous Baker Street sleuth who talked to me about his father who died in January and on the day that Avengers legend Patrick McNee died in the US.

"Lots of people don't realise how much that dad has written," says Sam about his 83-year-old father. "A friend was thinking about writing a book with him before he passed away and research on dad showed that he might hold the record for the most things produced to date of any writer on TV and film. The volume of things he has written is colossal and it's no surprise that people say, 'I had no idea he'd written this play'."

Brian was commissioned to write Sherlock Holmes in the 1970s by John Newman and Francis Matthews played Holmes back then. The play was revived in 2008 and Sam agreed to take part in the cast for a thriller season in Nottingham.

"I didn't play Sherlock. I was a character called Ewan Goddard. Patric Kearns, of Talking Scarlet Theatre company had talks with my dad about a tour and it was a lovely surprise and equally terrifying when I was asked to play Sherlock," says Sam.

He and brother make films under the names of Clemens Bros and hold the rights to many of their father's famous TV projects such as The Professionals.

"We're slowly discovering what we rights to. A lot of people think we own The Avengers but they are actually owned by Canal Plus, but we do own The Professionals and there is talk of a movie happening. There are so many things that dad wrote that were never produced. His favourite script is for a film called The Long Road West which is about a young American cowboy in a PoW camp in the Second World War and he teams up with an older Russian prisoner to escape Nazi-occupied Europe on horseback pursued by the Prussian army. We've just done a film which was dad's last idea and we honoured it by making this ten-minute horror called Surgery," says Sam, who got the financially backing through Crowdfunding.

While Brian created some of the great Hammer Horror film scripts like Dr Jekyll and Sister Hyde (1971), he is still affectionately remembered by a generation of baby boomers for an output of TV favourites from Danger Man, Adam Adamant Lives! and The Baron to The Persuaders!, My Wife Next Door, The New Avengers and contributed to Bergerac, Remington Steele, Perry Mason, Diagnosis Murder and BBC sci-fi series Bugs.

"One thing that is still impressive about The Avengers today is that it is the only British TV show to do well on primetime American TV. So that was pretty awesome," he says.

Moving on to the play itself, the idea of putting Sherlock Holmes on the case of Jack the Ripper has captured the imagination of film-makers with Murder by Decree, in 1979, starring Christopher Plummer and James Mason as the detectives.

"It's an interesting marriage and from the same period, so it makes sense. Dad's version is based on Stephen Knight's book The Final Solution from 1976 which has also been explored in the film From Hell. But dad wrote the first version which has an interesting and dark edge because you are dealing with reality," Sam says.

For that reason, the plot does reach a conclusion but “it cannot be made public knowledge. So, Sherlock gets his man, but Watson has to put down his pen on this occasion.”

His co-stars are Holby City’s Neil Roberts with Emmerdale’s George Telfer as Watson and Sam is quite modest about his own billing because he feels that the names of Holmes and The Ripper will put enough “bums on seats” to justify a large cast (11) taking to the road for a summer season at Darlington.

“Once dad passed away, Patric said he wanted to make it a tribute to him and that’s why he asked me to play Sherlock. I’m an actor and Tom Hardy was in my year at The Actors’ Centre and he’s done all right,” he jokes.

The main thing that Sam’s company brought into the project was film composer Edward White to create some original music for the show and concept artists to made projection art for the stage.

“We are rehearsing that today, and I’m not going to lie with a week’s rehearsal for something this large, I am being pushed to my limit. I think you have to play Holmes from who you are rather than think about someone like Benedict Cumberbatch who is quite a strange-looking individual and made a decision to bring a slightly asberger’s side to the role. Johnny Lee Miller does Holmes as a slightly unhinged individual and both are very modern. Dad wrote this in the 1970s and his Holmes is quite traditional and someone who is incredibly observational and quite emotional at times. Jeremy Brett and Basil Rathbone are also hard acts to follow, but you’ve not got to worry about them,” Sam says.

Returning to dad, he reveals that the brothers were far from happy with tributes paid to Brian by the entertainment industry.

“We had a bit of a spat with Bafta not mentioning him and not having him in the remembrance piece in the film awards, but they did remember him in the TV awards because we made a bit of a fuss. It missed out Bob Hoskins as well and Donald Sinden and it needs to think about who has gone before rather than thinking constantly about what is happening right now. Without them, the people after wouldn’t be there. There has been no big tribute to dad , but I’m sure they will be at some point,” says Sam. The BFI did celebrate Brian’s OBE in 2010 and the Frightfest Festival in Leicester Square will be screening Captain Kronos: Vampire Hunter.

“I remember my dad going to the BBC to discuss a TV show in the last ten to 15 years of his life and he mentioned a character the BBC wanted was ‘a bit Cary Grant’ and the young executive had no idea who Cary Grant was. I felt he probably shouldn’t really be in our industry if he didn’t know about Cary Grant.”

For tribute updates go to the facebook Brian Clemens page or twitter @clemensbros

n Sherlock Holmes & The Ripper Mysteries, Darlington Civic Theatre, Wednesday to Saturday. Box Office: 01325-486555 or darlingtoncivic.co.uk