a "great asset" to the cast, expanding: "His character will make waves from his very first scene and upset the apple cart of Holby City in more ways than one." Henry shadowed Daren Francis, a surgeon at a North London hospital and Holby City general surgical advisor, as research for the role. He described Hanssen as "punctilious, pedantic and passionate about his work", but with a dry sense of humour, essential for his rivalry of Connie. He explained that Hanssen is not afraid of making enemies and relishes his Machiavellian tendencies, attributing his fractious relationship with Connie to their mutual God complexes and arrogance. Henry considers Hanssen willing to goad people "to go out of their depth", with an ability to frequently "wrong-foot" others. What's on TV deemed Hanssen "Holby very own George Osborne". Hanssen was initially presented as an "unknown quantity", including to Henry, who knew little of his character's backstory. In an interview with TV Choice, Henry stated that he believed Hanssen to have come from a "rather unfortunate background". He was sent from Sweden to attend public school in Britain, possibly following the death of his mother, resulting in him becoming "a little more pedantic and English than the English." As of October 2010, his family and love-life had not been decided upon, but it was suggested to Henry that while Hanssen was at medical school, he entered a relationship which did not work out and had not had a romance since. Henry commented that it was possible Hanssen was gay or bisexual, and that an upcoming storyline with a younger female mentee may involve unrequited love. In November 2010, media entertainment website Digital Spy announced that Laila Rouass had been cast as Sahira Shah, a surgeon who shares a "dark history" with Hanssen, who has guided her career. Henry appears as Hanssen in a two-part crossover episode with Holby City sister show, Casualty, originally broadcast in March 2019. Departure On 25 August 2013, it was announced that Henry had decided to quit his role as Hanssen and would be leaving towards the end of the year. Henry said how "wonderful" it was to play Hanssen, because he is "such a weird man, but fun to play." He also commented on how delightful it was to work with the cast and crew of Holby City. Simon Harper also commented on Guy's performance as Hanssen: “His brooding, enigmatic