The aliases used by Christian Harper (played by Paul Blackthorne ) match starring and recurring roles Blackthorne had in other television series and movies. Namely, Guy Morton (Holby City), Liam McGregor (Peak Practice), Jack Quinn (Gramercy Park, a made-for-TV movie), Terrence Hill (Big Shots), Shane Healy (Lipstick Jungle), and Stephen Saunders (24).