Gemma's first acting role was when she joined the popular BBC soap opera EastEnders in 1993 playing Clare Bates, daughter of Debbie Bates and stepdaughter of Nigel Bates.
After leaving EastEnders in 1998, Gemma took a break from acting for a few years. In 2000 she guest starred in the Doctor Who radio drama, The Fires of Vulcan. In 2002 she returned to television guest starring in an episode of the medical drama series Doctors. She then played Sadie in an episode of the CBBC show The Crust.
Gemma also appeared three pantomimes and various adverts before working in Marks & Spencer as a bra measurer
In 2006 she joined the cast of Hollyoaks playing, incidentally another character called Clare, this time Clare Devine (later Cunningham). She replaced Samantha Rowley who was axed after playing the role during 2005.
At the 2007 British Soap Awards Gemma was nominated for 'Villain of the Year', 'Best Actress' and was also nominated for 'Most Spectactular Scene of the Year' for Sam O'Brien punches Clare and 'Best Storyline' for Clare tries to kill Max.
In the end Gemma won in one of the four categories she was nominated in. She walked away with the 'Villain of the Year 2007' award for her portrayal of Clare Cunningham. She left the soap in 2007.
On 19 September 2007, it was announced that Gemma will be reprising her role as Clare Bates in EastEnders. She will return on-screen on 1 February 2008.