Freya has been appearing on the BBC One drama since May, when she was introduced alongside fellow newcomer Kevin Tyler (Simon Rivers).
Corfield told Diva Magazine of her alter ego's future: "On screen, up until now, Freya has been seen as a reactor and an accomplice - pushing along other characters' storylines.
"This month, that changes in a big way. The scripts start to focus on finding out who she really is - underneath all of those checked shirts."
The actress said that yesterday's episode 'Parts and Fitters', which saw Cherry discover Freya's relationship with male 'friend' Bobbie, was "the start of a major storyline for Freya".
Corfield continued: "Between now and February, a lot will be revealed about Freya. Kevin helps to unravel a thread exposed in 'Parts and Fitters', Cherry and Freya hit some turbulence and I've just started filming with someone who is going to turn Freya's life upside down."
Doctors airs weekdays at 1.45pm on BBC One.
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