Ant & Dec discover one of them is related to royalty in new ITV show Ant & Dec's DNA Journey.
The two-part special will see the UK’s best loved duo embark on a surprisingly emotional journey of discovery.
ITV tease that "viewers will see Ant and Dec navigate a tougher terrain than the Australian jungle" in the upcoming show.
Guided by expert genealogists and historians, the pair will follow their maternal and paternal blood lines using their DNA to search their ancestral history.
Ant & Dec's DNA Journey will air tonight at 9PM on Sunday, November 10 and continue Monday, November 11 on ITV.
A synopsis reveals: "As their travels take them to Ireland and the US, including The United Nations Headquarters, the pair will not only delve into their past but will also meet relatives they had no clue even existed, unveiling some truly shocking revelations that only their DNA could unlock.
"Whose great grandfather is a celebrated war hero and whose DNA cousin is a former US female wrestling promoter?
"Whose ancestors’ bones were deemed ‘of historical importance’ and who discovers that they are a descendant from Royalty?
"As Ant & Dec embark on their journey, viewers will be treated to a rare and personal glimpse into this truly remarkable friendship with their warmth and infectious humour that has not only captured the nation over the years, but has seen them achieve huge success resulting in a multitude of awards and accolades."
Ant said: “I’m a bit of a geek when it comes to historical events, so to get the chance to research our family history using our DNA was too good an opportunity to pass up.
"What we find out is mind-blowing and nothing either of us could ever have imagined. It’s something that will stay with us both forever. "
Dec added: “A huge part of this was to find out my heritage, especially on my dad’s side. I always thought I knew a fair bit about where I came from but it turns out I was wrong! Whilst it was incredible to find out about the past, what was hugely overwhelming was to meet relatives neither of us knew we had. It was a truly amazing experience."
Kathleen Larkin, Executive Producer from programme makers Voltage TV said: “It’s been a privilege working with such talent as Ant & Dec. This is a film that celebrates friendship, showing two brilliantly funny best mates making a unique trip of a lifetime to find out about their heritage past and present.
"It’s been a passion for all involved and we’ve loved working with the fantastic team at ITV to make something we all believe in.”
Ant & Dec’s DNA Journey will air Sunday and Monday November 10 & 11 at 9PM.
You'll be able to watch the show online via ITV Hub.