December sees a web of secrets, lies and revenge being unraveled as McKee's character Louise Summers prepares for her wedding to fiancé Warren Fox (Jamie Lomas).
However, beneath the tough, bitchy exterior lies a dark secret which is about to be outed. After discovering Warren's affair with best friend and bridesmaid Mandy (Sarah Jayne Dunn), Louise formulates a plan and acquires a gun. Will she target Mandy or Warren? Or will the plot resolve come to its head in an unsuspecting and twisted way?
Speaking of her decision to quit, McKee said: "I have enjoyed my time at Hollyoaks immensely and I’m going to really miss everyone at Lime Pictures.
"I have learned so much and will take away with me many happy memories - not just from everyone I have worked with but from Liverpool as a city too, which has become my second home. I know I will shed a few tears on the day I leave but I am so excited about what the future holds."
Producer Bryan Kirkwood said: "As well as being the nation’s sexiest soap star for two years running, Roxanne has worked incredibly hard to prove herself as a talented actress. She has been at the centre of one of our biggest storylines for the past two years and her exit scenes will be a fitting climax."
He added: "Roxanne is a real star in the making and I’m sure this won’t be the last that we hear of her.”
The end of the year also sees the departure of producer Bryan Kirkwood after three years heading up the Lime Pictures production.
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