She made her acting debut in the television police series The Bill and rose to prominence for her role as Kat Slater on the BBC soap opera EastEnders (2000–2005, 2010–present).

She also portrayed the role of Pat Phoenix in the BBC Four television film The Road to Coronation Street, for which she was nominated for the 2011 BAFTA TV Award for Best Supporting Actress.

[5] After schooling, Wallace trained as a make-up artist at the College of North East London in Tottenham and worked at the Royal Shakespeare Company for two years.

[5] While undertaking auditions – including for Andrew Lloyd Webber's Sunset Boulevard, she worked as a barmaid at her local pub, The Royal Oak in Loughton, Essex.

Speaking about the show, Wallace commented: "I have always loved working on EastEnders so when I heard of this new drama to take Kat and Alfie outside of Walford, I couldn’t believe our luck.

"[14] However, Wallace and Richie later revealed on This Morning in January 2016 that Kat and Alfie would not be returning to EastEnders after the six-part drama, and the characters departed at the end of that month.

[17][18] During her break from EastEnders, Wallace made television guest appearances, including once as Kat Slater, in the 2005 French & Saunders Christmas special.

[1] In 2007, she appeared in the one-off BBC One television dramas A Class Apart opposite Nathaniel Parker, and The Dinner Party with Lee Evans and Alison Steadman.

[34] In July 2015 it was announced that Wallace would appear alongside Richie in a stage adaptation of The Perfect Murder by Peter James at the Theatre Royal in February 2016.

[38] The BBC offered her counselling and while attending county court for sentencing, she was accompanied by a policeman, Dave Morgan, in case she was accosted by fans.

[39] In a tabloid story that surfaced in September 2007, whilst Wallace was filming Wild at Heart in Johannesburg with her cousin Jonathan and daughter Tallulah, her best friend, Stefan, suggested she still regularly took ketamine.