Harry Sullivan is a doctor and general practitioner who helped an injured fisherman get to safety at Knapford by both helicopter and train.
Harry Sullivan introduced himself to Harold as the town's general practitioner of Kirk Ronan. He flew with the injured fisherman to a part of The Main Line where they caught sight of Donald and Douglas chuffing with a goods train to the docks at Brendam from Barrow-in-Furness and the helicopter landed next to them. He told them about the bad weather and the two men were on their brake van ready to head for Knapford. Alice was asked by the new controller, Sir Stephen Topham Hatt to wait with the express as the Scottish twins brought the doctor into the station. He later told them about the flood on the road from Kirk Ronan up to Knapford and moved the injured fisherman down to the ambulance and was taken to the hospital in it.