The new series of DNA Journey begins airing on ITV at 9pm on Wednesday 9 October.
In the first episode, actors John Simm and Philip Glenister will trace their family history together.
The long-time friends have starred in five different productions together, most famously the time-travelling police drama Life on Mars.
However, as John Simm explains, he had a shock when they began making the programme. A DNA test revealed that his father, who died in 2015, is not his biological father.
He says his mother said that she and his father were in a relationship, then broke up, then got back together and had him, so she knew that there was a possibility that another man she was involved with could have been his biological father.
“It spun my world,” he says. “Everything I thought I knew wasn’t real, in a way. Out of everybody in my family, I was always closest to my Dad. When I was younger, we used to go around clubs playing guitar and singing. I’m glad my Dad isn’t alive to see this, because I’m sure he’d be shocked and upset by it as well.”
However, he says he wants to carry on with making the programme and find out more.
“Even in this, you have to upstage me,” Philip jokes.
His birth father was a man named Terence Naylor. John and Philip go to Featherstone in Wakefield, where they meet a family historian called Brad. Philip tells them that Terence, also known as Terry, died in 1998. Terry’s parents married in 1939 and he was born in 1940 while his father was serving in the Second World War. Their marriage subsequently broke down and Terry was adopted by his birth mother’s aunt and her husband, who lived in Featherstone. Despite an inauspicious start in life, he had a loving upbringing in his adoptive family.
John says that he and his father played in clubs in Featherstone and wonders if Terry ever saw them.
They go to Girnhill Lane Working Men’s Club in Featherstone, where Ian Holt, the club’s steward, tells them that Terry also lived above a working men’s club that was run by his adoptive parents. John is amazed at the coincidence, as he “grew up” in working men’s club dressing rooms.
Seeing a picture of Terry, John and Philip are surprised by how much John looks like him. John is also astonished to learn that Terry was married and had a daughter, Karen, John’s half-sister.
John says he’s keen to meet her: “If I don’t, I would probably regret that for the rest of my life.”
Next, John and Philip go to Chelmsford in Essex to find out more about Philip’s family history. Philip’s jokes that he hopes he finds out he’s inherited a fortune.
They meet a family law barrister called Paula. She tells them that Philip’s 5x great grandfather was Samuel Bundock, an Essex farmer. Samuel became wealthy from producing food for sale in London, which grew rapidly in the 18th century. However, his will shows that he only left his son John, Philip’s 4x great grandfather, a paltry £10.
“That’s it, then,” Philip says. “The Bundock billions, gone!”
John and Philip go to a shoemaker’s in Shoreditch, London, where they meet a historian called Simon. He tells them John’s daughter Ann Bundock, Philip’s 3x great grandmother, was born in Shoreditch. She married William Glenister, a shoemaker. They had 11 children – one of whom, Margaret Glenister, found fame as an opera singer, under the stage name Pauline Rita.
Pauline temporarily stepped back from the stage after she married in 1870. But her husband, Thomas Phillips, then died, so she had to return to singing to provide for her children. She made a tremendous comeback, starring in one of the first tours of Gilbert & Sullivan’s opera Trial by Jury.
Finally, John and Philip meet John’s half-sister Karen and her daughter Stacey. Karen shares memories and video footage of Terry.
