The 80-year-old actor, who has played Weatherfield's Ken Barlow for 52 years, will appear in the current series of the family history programme later in the autumn.
The Ilkeston Advertiser reports that the star's trail includes an interesting tale about his maternal grandmother Zillah Waddicor, a businesswoman who ran Alton Towers as a stately home between the World Wars.
Producers of the BBC show decided to focus more attention on his mother's side of the family, which took him out of Derbyshire.
Samantha Womack and Gregg Wallace have been the first two faces on Who Do You Think You Are? this year, with the popular show continuing for the next six weeks.
Next week's edition will feature Star Trek actor Patrick Stewart, airing in its usual Wednesday 9pm slot on BBC One.