Since his arrival in the village last August, Brendan (Emmett Scanlan) has managed to keep Cheryl convinced that he is straight - while secretly maintaining a complex and abusive relationship with barman Ste Hay (Kieron Richardson).
However, in an online webchat with Heatworld this afternoon, Waugh explained that all will be revealed to Cheryl within the next few weeks.
Asked how Cheryl would react to Brendan's secret, Waugh replied: "I don't think she would be unhappy about him being gay. I think she would be absolutely devastated to find out that he's been lying to her for so long.
"Actually, in the coming weeks, all is going to be revealed and Cheryl is going to have a bit of a nightmare when her whole world as she knows it comes crashing down, so watch out."
The actress added that Cheryl's discoveries about Brendan leave her stunned and "seriously rock her world".
She added: "I don't think she's upset by the fact that he's gay, it's more the fact that he's been keeping it from her."
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