Sam Mitchell is a fictional character from the BBC soap opera EastEnders. The third member of the Mitchell family to appear on the soap, Sam was introduced as a 15-year-old schoolgirl in July 1990, originally played by Danniella Westbrook. Westbrook quit in 1993, but Sam reappeared from 1995 to 1996 and from 1999 to 2000. In both stints, Sam was written out earlier than the producers intended due to off-screen controversies surrounding Westbrook. In January 2002, Sam was introduced for a fourth time, but the role was recast to Kim Medcalf, who stayed in the role until November 2005. Diederick Santer later decided to reintroduce Sam for a brief stint in 2009 and opted to bring Westbrook back. Westbrook briefly reprised the role once again in 2016 for the funeral of Sam's mother Peggy Mitchell. In January 2022, it was announced that Sam would be returning to the show, this time played by Medcalf again. Medcalf’s return scenes aired on 18 April 2022. Medcalf took an extended break from the show in 2023, with Sam departing on 13 April 2023 and returning seven months later on 21 November 2023. On 18 January 2024, Sam made an unannounced departure from the show following Medcalf's decision to leave indefinitely.

Peggy Mitchell is a fictional character from the BBC soap opera EastEnders. Peggy was initially played by Jo Warne when she first appeared in the episode broadcast on 30 April 1991, featuring in 10 episodes. Peggy was reintroduced in 1994, recast to Barbara Windsor, who made her first appearance in the episode broadcast on 7 November 1994. Peggy became a regular character, and Windsor played the role until she was forced to take a long break due to poor health and departed on 23 May 2003. She returned for two episodes broadcast on 16 and 17 September 2004, before rejoining as a regular character on 8 September 2005. Windsor announced in October 2009 that she would be leaving the show and departed on 10 September 2010. Windsor returned to the show for guest appearances on 20 September 2013, 25 September 2014, 17 February 2015 and 15 January 2016. She then appeared in six episodes between 9 and 17 May 2016, where the character was killed off. Her voice is last heard in the following episode, on 19 May 2016. Peggy's funeral aired on 4 July 2016. An archived recording of her voice was heard on 25 January 2022. On 26 July 2022, it was announced that Peggy would feature in a flashback episode set in 1979, alongside her husband Eric and their children Phil, Grant and Sam. Jaime Winstone played the role of Peggy for this special episode, which aired on 5 September 2022.