Royalty, murderers and God: 'Who Do You Think You Are?' most surprising celebrity ancestors
Who Do You Think You Are? viewers are still reeling from the revelations of the season 18 opening episode - as, presumably, is Josh Widdicombe.
The comedian discovered his uber-posh roots when genealogists revealed that he was a direct descendant of King Edward I, had an ancestor embroiled in a royal love triangle, and was possibly related to King Henry VIII.
Read more: TV viewers can't believe Josh Widdicombe is descended from royalty
Widdicombe's family tree read like a who's who of British monarchy, but while it was certainly one of the more memorable episodes, he isn't the first celebrity to have been presented with shock revelations on the BBC One show.
Widdicombe's episode drew obvious comparisons to Danny Dyer, whose royal connections were even more surprising.
The EastEnders star and gangster movie hard nut was expecting to hear about a tough London life for his ancestors, but instead discovered they had been some of the most privileged people in the land.
Read more: Danny Dyer is related to royalty
Dyer was told he was a direct descendant of both William the Conqueror and King Edward III, and was also related to Henry VIII's advisor Thomas Cromwell.
Even more entertaining than watching Dyer receive the news were the scenes when he went home to break his royal lineage to his disbelieving wife.
If one celebrity can put Widdicombe and Dyer's family trees in the shade, it has to be Matthew Pinsent who appears to be related to God.
The Olympic rower unsurprisingly had some pretty posh ancestors, including Henry VIII's wife Catherine Howard, and Edward I and William the Conqueror, just like Widdicombe and Dyer.
But the real shock came when an ancient scroll traced his lineage back to Adam and Eve.
The stand-out moments in actor Patsy Kensit's family tree were both much more recent, and much more grisly.
She already knew that her late father was an associate of some of London's most notorious 1960s gangsters, with Reggie Kray godfather to her brother.
However, she also found out that her grandfather was a prolific criminal, too - although other ancestors were artisans and one was even a vicar dedicated to helping the poor.
Harry Potter author JK Rowling's incredible rags-to-riches tale is well-known as she wrote her novels in Edinburgh cafes as a single mother to lift herself out of poverty and become one of the richest writers in the world.
So it was a truth stranger than fiction for Rowling to discover that she came from a long line of strong single mothers, including her great grandmother, great-great grandmother, and great-great-great grandmother.
One of the most heartwarming Who Do You Think You Are? episodes was EastEnders and Gavin & Stacey star Larry Lamb's.
The actor had signed up to the programme for his beloved mum, who at 84 had had a lifelong yearning to find out what became of her biological parents who gave her up for adoption as a baby.
Shifting into Long Lost Family territory, Lamb tracked their story over to the US and discovered a surviving brother for his mum, who had always believed she was an only child.
It comes as no surprise to anyone that the now-PM hails from a long line of privilege.
However, it turns out he's posher than even he suspected as he is a direct descendant of King George II and is related to Queen Elizabeth II, the Swedish and Dutch royal families, and famed Russian Imperial dynasty the Romanovs.
Another celebrity uncovering a murky past through the programme was opera singer Lesley Garrett.
She had believed her great-great grandfather to be a pillar of the community as a local councillor, but according to his son and daughter-in-law he had actually killed his wife by replacing her medication with carbolic acid.
Her death was ruled by a coroner to be accidental, but others seemed convinced it had been planned.
Who Do You Think You Are? continues on Tuesdays at 9pm on BBC One
Watch: Josh Widdicombe learns he is related to King Edward I