ANT and Dec break down in tears as they meet long-lost family members while filming special documentary DNA Journey.
The two-part special follows the Geordie duo as they tread through their family history with the help of historians and genealogists.
The documentary tracks their maternal and paternal bloodlines using DNA in order to fully explore their ancestral histories.
Their travels will take them from Ireland to the US, including the United Nations Headquarters.
Throughout they will meet relatives who have no idea they ever existed.
Alongside their individual family lives, it will also shine a light on Ant and Dec’s treasured friendship and how they became such remarkable friends.
The trailer gives a glimpse at the extraordinarily emotional journey both Ant and Dec will take.
It opens with the friends coming to terms with the gravity of their journey, with Dec Donnelly, 44, saying: “It’s not lost on us, how lucky we are that we met each other.
“We get on so well. I’m getting emotional now. I don’t know if I’m ready.”
Dec then says: “I’ve never cried so much on telly in all my life.”
It promises a journey for both them and the people who have been invested in their lives since they came on our screens in 1993.
In one scene, it shows Ant McPartlin, 43, becoming emotional as he realises his great grandfather – unknown to him – was a war hero.
While Dec traces his genetic steps through Ireland, and is told his DNA is “in the ground they walk on”.
Speaking about the show, 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 adds: “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.”
Ant & Dec’s DNA Journey airs in November on ITV.