Thomas Croft, the artist behind Portraits for NHS Heroes, meets Mark, a former Royal Marine who survived an explosion during a foot patrol in Afghanistan in 2007. The injuries Mark sustained resulted in a triple amputation - he lost both legs and his right arm. Despite this traumatic experience, Mark has become an inspiration. He is a charitable fundraiser, a mentor and role model to other amputees and an ambassador for the Royal Marines Association. Thomas is renowned for his ability to tap into the emotions of his subjects, and together he and Mark explore how we perceive bravery, masculinity and family.