Actor John Simm poses for a happy family photo with the man he idolised and had always believed was his father.
One relative even described the pair as being like 'two peas in a pod' after the image was posted on social media.
The photograph emerged after Simm revealed that at the age of 54 his life has been turned upside down after he discovered that Ronald Simm, the man who had lovingly brought him up, is not his biological father.
The bombshell revelation came after the actor signed up for ITV show DNA Journey and took a genetic test.
He only agreed to appear in the programme as a favour for Life on Mars co-star Phil Glenister so they could research their family trees together.
Actor John Simm poses for a happy family photo with Ronald Simm the man he idolised and had always believed was his father
John Simm's true biological father Terry Smith is pictured after the revelation was made on part of a DNA Journey episode
Simm said of the the life-changing discovery - which could have come straight from the script of an episode of the time travel detective series set in the 1970's: 'Everything I thought I knew wasn't real.'
The star also learned he has a half-sister he never knew about and that his biological father probably saw him perform on stage in the 1980s.
While rarely talking about his private life, Simm has previously spoken of his working class upbringing with mother Brenda, 75, and Ronald who died in 2015 aged 79.
Simm was born in Leeds on July 10th 1970 and was registered with Ronald as his middle name. Brenda was aged just 21 at the time.
Recalling a conversation he had with his mother, Simm explains on the programme: 'When they had me, in the Sixties, they were both young. They were together and then they split up and were both with other people and then they got back together and then they had me. And I'd never heard this story before.'
Although born in Yorkshire, Simm spent most of his childhood across the Pennines in Lancashire living in various locations before the family settled in the former mill town of Nelson where he has told how they lived in a terraced house with 'an outside toilet'.
The couple went on to have twin daughters Carole and Nicola, now 49, who were born five years after the actor.
Simm - who has also starred in Doctor Who and in the detective series Grace - has said of his formative days: 'I had a great childhood, we were very poor, but we played out and we had so much fun.'
While rarely talking about his private life, Simm has previously spoken of his working class upbringing with mother Brenda, 75, and Ronald who died in 2015 aged 79 (Ron and Brenda seen)
Ron and Brenda are pictured together
Philip Glenister (left) and John Simm (right) on ITV's DNA Journey which will air on October 9
John also learns that he has a half-sister Karen whom he meets on ITV's DNA Journey
John Simm (left) appeared on the show to support Life On Mars co-star Philip Glenister (right)
John (left) took a genetic test for ITV's DNA Journey alongside co-star Philip
Ronald was a musician who played the working men's club circuit and the pair grew close when Simm began joining him at weekends.
Simm was aged just 12 when they started performing together as a double act playing guitar and singing along to Everly Brothers and Beatles songs and continued until he made a break for the big time, heading off to London to study drama aged 18.
Read More Actor John Simm is stunned to discover his beloved dad was NOT his biological father during emotional episode of ITV's DNA journey
Simm has told how Ronald was 'left heartbroken' when he left and speaking of their bond he once said in an interview: 'When someone dies, you're left with this huge black hole in your life.
'People say, 'You'll get over it,' but I don't want to get over it. I always want to remember my dad. I've still got his number in my phone.
'Every so often I see something on TV that I think he'd like and I pick up my phone to text him, still.'
During the programme, Simm learns that his biological father is Terence Naylor from Featherstone in West Yorkshire who died in 1998.
But Simm believes he may have unwittingly met him while on the road with Ronald after learning Terence, who was known as Tel, used to drink at the same clubs, and even lived above one.
In the programme - which will be screened next week - Simm said: 'We played around here loads of times and he might have been in the same pub one night and watched me play.
'I can't get it out of my head, because we played this area in the 80s and he was here. It's one of those mad, Back to the Future, Life on Mars things.'
Meeting up with his half sister Karen, Simm learned that Terence also loved getting up on stage and singing.
Speaking to Karen, Simm said: 'If he happened to be in on a Friday or a Saturday night in one of those clubs, he would have seen me play. Wow, that's mad, isn't it? Yeah, that's really bizarre. Mind-blowing.'
Asked how the revelations had made him feel, he added: 'I mean, I was really close to my dad. He was like my best mate.
Philip Glenister (left) and John Simm (right) are friends and Life On Mars co-stars
Philip Glenister played DCI Gene Hunt and John Simm played DI Sam Tyler in Life On Mars
John Simm and his wife Kate Magowan at an English National Ballet party in London in 2013
'But having said that, there was always something, I really felt different.
'And I always felt a bit guilty about it. But a lot of things sort of fall into place. I kind of feel not guilty about feeling different.'
Father-of-two Simm - who is married to EastEnders actress Kate Magowan, 49 - considered quitting the show after making the discovery but decided to utilize the experts for information on his real father.
He said of the discovery: 'I'm glad my dad isn't alive to see this because I'm sure he'd be shocked and upset.'
Mum Brenda was also 'absolutely floored' by the news.
