Coronation Street will leave fans reeling next week with a shocking betrayal.

Warning: spoiler alert!

Viewers will see Daniel Osbourne (played by Rob Mallard) kissing Bethany Platt (Lucy Fallon) after he has an argument with his terminally ill wife Sinead (Katie McGlynn).

Next Monday night's drama sees Daniel and Sinead celebrating an early Christmas so that their infant son Bertie will be able to look back on the three of them together.

Daniel and Sinead have an argument when he tells her to rest and she then tells him to get out of the flat. 

While getting some air Daniel is comforted by the smitten Bethany - and then leans in for a kiss.

The kiss is interrupted by Daniel's father Ken (William Roache), who orders him to go home to Sinead.

Fans can find out what happens next in the love triangle on Virgin Media One and ITV on Monday, October 21. 

Actress McGlynn has said that portraying Sinead, who was diagnosed with cervical cancer while pregnant, has taken its toll.

"You can't switch off really," she told the Press Association of her final scenes.

"I've recently just suddenly got really sad and I actually feel like I'm grieving, where you get waves of sadness.

"It is hard to watch. When we were in that room it just felt real for us. In order to get yourself to that place, we felt like somebody had actually died."

When asked if she thought the storyline would have a lasting effect on her, McGlynn replied: "I don't take life for granted as much as I did, I guess. I've been a bit more emotional with my friends and family, as in more caring and loving."

Coronation Street has worked with UK cancer charities on the storyline with the episodes on Thursday, October 24 and Friday, October 25 devoted to Sinead and her family. 

Producer Iain MacLeod said: "It felt like the respectful way of doing it and the most interesting way of doing it and the least soapy way of doing it was to just be in there really and see the difficulties they both experience, see the moments of laughter that were still in there, the moments of warmth and just let it tell its own story and take its own time.

"It was a conscious decision not to fast forward that. I also feel like after you've told a story for two years or 18 months it would be remiss to gallop through the end."

If you have been affected by issues raised in this story, please visit: www.rte.ie/helplines.

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