Chelsea Halfpenny
Halfpenny's professional acting career began in 2004 when she appeared in "Casualty" episode ""What Parents Do"", playing an eleven-year-old girl called Karine.
Characters of Casualty
The character and Spearritt's casting was announced on 18 December 2015, with Mercedes described as "mysterious". Spearritt, who was most known as a singer in the pop band S Club 7, had previous acting experience in "Primeval". Following the announcement, Spearritt wrote on social network, "Twitter": "I'm so happy to say i've joined the BBC Casualty as Mercedes Christie...very excited! @BBCCasualty". Spearritt described Mercedes as "edgy and manipulative" and commented that she was "different" to her previous roles and "potentially a bit of a challenge". Spearritt revealed that after her audition for the role of Mercedes she was "all teary" and spent days in a "self-conflicted isolation", hoping she had won the part. For the role, Spearritt "grimed" herself up and bought several hair braids, nose rings, ear cuffs, "hippy-themed" earrings amongst other items. Spearritt also dyes her hair lilac weekly for continuity reasons. Spearritt described her first scenes as "pretty action-packed" and "fun" to film. She also praised the cast and crew for being "warm and welcoming".