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
Sam Mitchell (EastEnders) buried Den's body in the Vic cellar and Sam proceeded to blackmail Chrissie and was then framed for Den's murder by Chrissie. The culmination of the plot - which saw Ross Kemp and Steve McFadden return to "EastEnders" as Phil and Grant to exonerate Sam - signified the departure of Kim Medcalf, who opted to leave the serial in 2005. Medcalf's final scenes aired on 17 November 2005. Westbrook returned to the show in 2009 in part of a shock storyline. Speaking of her comeback, she said, "I'm really happy to be coming back, it feels just like coming home.