Only the third time in this series that female nudity has been shown: a long-distance view through a window of a pair of breasts near the start of the episode.
Nickolas Grace plays Hugo Greening in this episode. He previously played the role of Frank Mannion in episode 3.3, Judgement Day (2000).
Julian Wadham plays William Chettham in this episode. He previously played the role of Simon Fletcher in episode 2.1, Death's Shadow (1999).
Jane Booker plays Janet Lovell in this episode. She previously played the role of Laura Hutton in episode 1.2, Written in Blood (1998).
Angela Down plays Dr. Goring in this episode. She previously played the role of Pru Bennett in episode 3.2, Blue Herrings (2000).