Tina O'Brien has said that her character Sarah will be "off the scale scared" when she confesses to being unfaithful in next week's Coronation Street.

Over the last few months, Sarah has given in to temptations and slept with bad boy Damon (Ciaran Griffiths), with husband Adam (Sam Robertson) none the wiser.

Things come to a head next week, however, when Sarah's young son Harry catches her kissing Damon in their flat and later starts to make odd remarks in front of a confused Adam.

"She compounds the problem and basically tries to convince Harry that it didn't happen or maybe he's imagined it," explained O'Brien.

"She pretty much tries to gaslight him which is followed by major, major guilt and I think that a realisation that she can't she can't do this anymore, this isn't right and she can't behave like this."

Seeing what her deception has done to her son, Sarah finally plucks up the courage to come clean to Adam about sleeping with Damon.

"It's just the worst and the guilt is incredible," O'Brien continued. "When she tries to explain to Adam why, she confesses it was lust basically, it was an escape from just being someone's mum, someone's wife, someone at work.

"She's just basically about to throw grenade into the marriage, so I think 10 out of 10, she's off the scale scared.

"She knows it's coming, she knows she's got to sit down and she knows she's got to tell him but it's that anticipation and the fact she knows he hasn't got a clue as well.

"The guilt, the feeling of disgust at herself and also the realisation that she could potentially have ruined everything are just overwhelming because she does still really want to be with Adam."

The scenes play out next week on Coronation Street, Monday, Wednesday and Friday at 8pm on ITV1 and ITVX.

> Picture Spoilers: Next week on Coronation Street (Jun 5-9)