Casualty fans will be left appalled this week when their favourite couple Charlie and Duffy hit the rocks.
BBC viewers should prepare to be shocked as reliable, kind and loyal Duffy cheats on her husband this Saturday (27 October).
Amid a dark storyline about her battle with depression and refusal to seek help for it, Duffy seeks solace in childhood sweetheart Bill.
And, after a night chatting about the past, they end up in bed together.
Duffy will be mortified when she subsequently wakes up in a hotel room after the one night stand.
It's grim, old stuff. We've known each other for so long. When you are playing scenes like that, you are being real in the moment.
Her big betrayal follows a run-in with Charlie last week, which saw him discipline her over a near-fatal mishap.
However when a shame-faced Duffy attempts to leave the hotel, she hears a cry for help and rushes to help a young woman taken ill at the hotel swimming pool.
And, when Ruby and Iain arrive at the scene, Duffy feels totally awkward because of the real reason she was at the hotel in the first place.
After lying to the pair about her reasons for being there, Duffy is forced to face up to her guilt when she is greeted by Charlie at the ED.
Can she keep the truth from him?
Now Cathy Shipton, who plays Duffy, has told Digital Spy that she struggled filming the scenes where her character Duffy cheats on Charlie...
She said: "We are looking at deception and cheating here. It's not nice to play. I felt very strange just doing the scenes with Derek [Thompson, who plays Charlie]. Just standing there and basically being a big, fat a liar!"
She continued: "It's grim, old stuff. We've known each other for so long. When you are playing scenes like that, you are being real in the moment. It's dark stuff that you pull up to perform. However, a lot of people also say it's great drama and that is the nature of the show."
Cathy also admitted that while she enjoyed filming the scenes as they are challenging as an actor, she empathises with viewers who'll think: "Here we go. They build them up just to break them down."
She also joked that the actor who plays Bill will "have to go into hiding" when the scene airs.
She said: "Clive - who plays Bill - says he is already getting funny looks in the supermarket just from the first episode they meet very briefly. He's just going to have to go into hiding tomorrow!"
Can you empathise with Duffy or are you angry with her? Leave us a comment on our Facebook page @EntertainmentDailyFix and let us know what you think!