Iain Dean is a fictional character from the British medical drama Casualty, played by Michael Stevenson. He was first introduced in a Red Button episode, which explores Sam Nicholls's fictional backstory as a medic in the army, alongside Iain with whom she is having an affair. The character then made his first appearance in the main show in the twenty-sixth series episode "Appropriate Force", broadcast on 28 April 2012. Iain gives evidence during a General Medical Council hearing, after Sam is accused of assaulting a patient. He returned in August 2013 this time as a trainee paramedic, who works alongside Jeff Collier and Dixie Dixon . He is also reunited with Sam, who is now in a relationship with Tom Kent . Stevenson confirmed that Sam was Iain's reason for coming back to Holby, and that he had hoped to start up their romance again. In November 2013, the character was the focus of another Red Button special, which helped to mark Remembrance Day and explore Iain's time in the army and relationship with Sam. It later emerges that Iain has posttraumatic stress disorder from being one of two survivors of a suicide attack in Afghanistan. Stevenson was pleased to have the chance to look further into his character's backstory. Following an incident in which Iain is held hostage and Big Mac is injured, he leaves Holby in the episode broadcast on 22 March 2014.