Peter, played by Chris Gascoyne, finally gives in to temptation by kissing Tina McIntyre following days of chemistry between the pair.
Viewers have seen the two characters grow closer since Tina started working as a babysitter for Peter's son Simon.
With Tina and Peter quickly falling for each other, fans will have to tune in this evening to find out whether Peter will go ahead with the ceremony. Could the womaniser's feelings for Tina crush Carla's dream of a perfect wedding day?
Speaking recently about the wedding day drama, Tina's portrayer Michelle Keegan commented: "Tina's anxious. I think she's really nervous about how the day is going to pan out, how it's going to make her feel and how she'll cope if Peter does go through with it and marry Carla. She's on absolute pins as she waits for him and Carla to turn up for the wedding."
Asked how Tina would feel if Peter goes through with the vows, she replied: "It would kill her, I don't know whether she'd be able to stay around and watch their marriage unfold. The thought of being the 'other woman' pains her so much. but I think the thought of not being near him at all hurts her even more."
Coronation Street airs a special hour-long episode tonight from 7.30pm on ITV.
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