Comedian and art lover Bill Bailey matches a life-saving railway worker with a celebrated artist to create a well-deserved portrait. East Londoner Rizwan stopped someone trying to take their own life in his first week of working for London Underground. In eight years, Rizwan has stopped another 28 people from coming to harm. His training teaches him how to spot vulnerable people, but his gift is how he relates to them individually. Attempting to capture this remarkable man in a portrait is multimedia artist Jack Dickson, who describes himself as an 'artistic magpie'. He collects clues about his subjects' lives and then builds them into multilayered visual artworks. What will Rizwan and his family think of the finished result?