Naman Ramachandran Jodie Whittaker, David Walliams, Liz Carr and Ruth Jones are the participants in the latest iteration of long-running BBC genealogy show “Who Do You Think You Are?” that returns in October.Produced by Warner Bros Television Production U.K.’s Wall to Wall Media, the two-time BAFTA-winning format follows U.K. celebrities who unravel their family histories.