Billy Mitchell (EastEnders) revealed in 2006 that the role was extended by "coincidence and chance": "I was offered four episodes and here I am, about 800 later. [...] Ross Kemp (Grant) said that he was leaving, and there was a gap in the Mitchell family, so they brought me back to do stuff towards his leaving. After that they offered me a year." Billy was reintroduced in 1999, making recurring appearances. He was involved in the leaving storyline of Grant Mitchell in October 1999, before returning later in the year as a regular character. When Billy was first introduced, he was depicted as
Ross Kemp in Afghanistan of the second series, 5 SCOTS and Kemp are ambushed by the Taliban within 30 minutes of his first patrol, targeted by small arms fire and RPG rockets, as well as mortars. Kemp is extricated to safety by crawling 50 metres along a ditch. In a later contact, after coming under fire, Kemp unwittingly ran into an area Kemp described as "probably" featuring the pressure plate devices used to detonate IEDs and mines, necessitating 30 steps back to the cleared area. During the filming for the second series, 100 metres from the crew a 22-year-old Royal Marine was fatally wounded