Hugh Bonneville discovers his Irish roots in a new episode of "DNA Journey."

Bonneville, an English actor, is paired with Liverpool-born comedian John Bishop on the ITV show, which will see four celebrity pairings unearth their past together in the fourth series.

Get ready for Season 5 of DNA Journey! 🚨🚨

Watch from 9pm this Tuesday 7th March - on #ITV1 and #ITVX #DNAJourney

— ITV (@ITV) March 4, 2023

The first episode, which premieres on March 7, will see Bonneville and Bishop, who became pals after a chance encounter in a COVID vaccination center during lockdown, go on an adventure together to discover their family history, reports the Irish Examiner.

The two are astonished to discover that their ancestors worked on the same street in Dublin and may have even marched together in support of workers’ rights as trade union men.

Accent schmaccent.#DNAJourney. Tonight at 9pm on @ITV 1 and @ITVX.

— Hugh Bonneville 🇺🇦 (@hughbon) March 7, 2023

Bonneville's ancestor John Freeman worked in a family bakery just four doors down from Bishop's ancestor Andrew Keegan’s music shop on Capel Street, Dublin, reports the Mirror.

“I thought it was a coincidence that you were at the vaccine center. To find out that generations before, our ancestors were working within 30 yards of each other... then to discover they were on a march together on the same day that started the path for discussions for Irish independence... staggering," Bishop says to Bonneville.

“That is quite spooky. It’s the sliding doors of fate and time," adds Bonneville.

“Not only are we friends, but I’d like to think that Andrew and John were friends back in the day.”

Bonneville, 59, who is best known for playing the Earl of Granthan in the "Downton Abbey" franchise, also learns about his ancestor Richard Bonniwell, who worked at London’s Somerset House and dedicated his life to improving working conditions for sailors in the 1820s, before building a school in Wales.

Meanwhile, Bishop, 56, uncovers his ancestor Patrick Reardon, who traveled from Ireland to Liverpool, and built a business in the booming salt industry.

Other celebrities taking part in the latest series of the show include "Line of Duty's" Adrian Dunbar and Neil Morrissey, comedians Alex Brooker and Johnny Vegas, and sisters Oti and Motsi Mabuse from "Strictly Come Dancing."

"DNA Journey" starts on Tuesday, March 7 on ITV and ITVX at 9pm.