Weatherfield bookie Peter Barlow (Chris Gascoyne) has been tipped to put his family life with wife Leanne (Jane Danson) in jeopardy in the coming weeks by embarking on an affair with Carla Connor (Alison King), while Karl Munro's relationship with Stella Price is also expected to come under strain in the New Year.
Speaking of Peter and Carla's future, Collinson told Inside Soap: "It's been a long story and I think we owe it to the audience to see them together. I genuinely don't know where that story is going, but they're two damaged people and it definitely isn't going to be an easy journey.
"Peter's caught between two women who offer him very different things - Carla's exciting and different and new, while Leanne is safe and familiar - and in every single way she's the best thing that's ever happened to him.
"Peter is brilliantly complicated and is never going to take the easy option, so there's certainly heartbreak in store for Leanne and Simon."
Collinson also said that the problems ahead for Karl (John Michie) and Stella (Michelle Collins) will be a big plot for early 2012.
"Karl has a number of secrets that Stella has missed, and the start of 2012 is going to be tough," he explained. "Karl may turn to someone else as he sets off on a dark journey which threatens his and Stella's future. It's a big storyline."
> Coronation Street Peter 'hits the bottle over Leanne'
> Coronation Street Peter Barlow scandal in store for Christmas
> Coronation Street star Chris Gascoyne reveals big Peter plans
> Coronation Street John Michie reveals gambling storyline
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