There is a character in this episode called Margaret Hopkins and Sergeant Dan Scott is played by John Hopkins. In the 17th century the infamous 'Witchfinder General' was Matthew Hopkins.
Jonathan Hackett plays Rev Jim Hale in this episode. He previously played the role of Reverend Thorne in episode 4.4, Who Killed Cock Robin? (2001).
Maggie O'Neill plays Agnes Waterhouse in this episode. She returns in episode 19.6, The Curse of the Ninth (2017), in the role of Audrey Glenhill.