The pair have found themselves firmly on the back foot in recent days as they have struggled to convince suspicious Eva Price (Catherine Tyldesley) that nothing has been going on between them.
With no proof, Eva has been forced to keep her theories to herself - but all hell breaks loose at The Rovers in late July as betrayed Stella (Michelle Collins) discovers the truth for herself.
Karl (John Michie) and Sunita (Shobna Gulati) will give in to temptation yet again later this month, but it appears that they have played with fire once too often when Stella walks in and catches them in a compromising position!
This time, there's no room for excuses or explanations - so how will Stella and Dev react to the shocking truth about Karl and Sunita?
Coronation Street airs the big scenes in a few weeks' time.