His mother and stepfather were hoteliers who ran a ski resort near the Swiss Alps. Despite their wealth, he refused any financial assistance from them. (AUDIO: Comeback) He visited them by boat rather than by plane. (AUDIO: Ghost Town)
As a young man, Josh set several buildings afire and apparently was good at it until he got caught. He later became involved with some unsavoury fringe groups, and spent eight months in Feltham Prison. After apparently cleaning up his act a bit and moving from one dead-end job to another (including McDonald's, Waterstones, and a printing press), Josh found his calling protecting Sarah from her enemies. He first met Sarah when he was 24 years old. In the the five weeks leading up to meeting her, he lost three mobile phones. (AUDIO: Comeback) He accompanied Sarah to the Huang Ti Clinic to find out what its connection with a dead teenager that looked 70. (AUDIO: The Tao Connection) He posed as a journalist for the Metropolitan to look round a medical research facility. He was later lured into a trap by Harris. (AUDIO: Test of Nerve) He hadn't flown before when Sarah took him to Romania on holiday. He didn't believe that Sarah had seen a ghost. (AUDIO: Ghost Town) He was going to paint Sarah's new flat. He was attacked when Hilda Winters' goons came to steal K9 Mark III. (AUDIO: Mirror, Signal, Manoeuvre)
He was glad that the business with Miss Winters was over when she died. He wanted to know why Sarah would go and see someone called Harry. Because of this he couldn't stop a buglary. He killed Luca Parenti. (AUDIO: Buried Secrets) He went with Sarah to Nikita Base after Will Sullivan invited them there. (AUDIO: Snow Blind) He helped to investigate Rechauffe when they needed to expose a new drug. (AUDIO: Fatal Consequences)
He had never handled a gun until he met Sarah, but killed to save her life on several occasions. He was her travelling companion, running around for her and sometimes using his credit card, provided by Nat, to sort out their transport.
When Sarah and Josh boarded the Dauntless space tourism flight, a member of the Crimson Chapter had infiltrated the spacecraft, and attempted to kill Sarah. However, Josh shot and killed the agent, but not before receiving a fatal gunshot wound to the stomach. Josh used his dying words to ask for forgiveness from Sarah, for not revealing his identity as an undercover agent for the White Chapter beforehand. She did forgive him, and he died shortly after. (AUDIO: Dreamland)
Josh was described by the vicar of Cloots Coombe as being stocky and dark-haired. (AUDIO: Comeback) Will Sullivan observed that his hair was long enough to wear in a ponytail. (AUDIO: Fatal Consequences)