Edward is a consultant anaesthetist who joins the AAU as a locum later this year.
Serena (Catherine Russell) isn't happy when she discovers that Edward has taken a position at the hospital. However, Edward is no stranger to charming his way through difficult situations and he tries his best to win her over.
Speaking of his new role, Gillett commented: "I'm looking forward to joining the cast of Holby. I've worked with Catherine, Guy [Henry] and Hugh [Quarshie] before, and it will be a pleasure to work with them again."
Holby City's executive producer Oliver Kent added: "We are excited to welcome Aden to the cast. His character will certainly stir things up for the usually unflappable Serena."
Gillett's previous projects include roles in The Borrowers, Silk and The House of Elliott, while he has also worked extensively on the stage.
Edward's first scenes will air in the summer.
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