However, Bleasdale was best known for his role as paramedic Josh Griffiths on the BBC television drama, Casualty. He was the second longest serving character in the show's 20 year history, bettered only by Derek Thompson's character Charlie Fairhead. Josh first appeared in episode 1 of series 4 (1989) and started as a speaking extra. His role has gone from strength to strength over the years and he has had several harrowing storylines so far, including the death of his family in a house fire, and his second wife Collette having an affair with a colleague and finally leaving him. He left the show on 3 November 2007 after 18 years. He has not been on TV in an acting role since but took place in the 2009 series of Celebrity MasterChef.
He appeared for a short part in one of the last episodes of The Bill.