Coronation Street is lining up a dramatic plot for Sally Metcalfe next week when she is told her cancer has come back – only to discover she’s been the victim of a sick prank by an online troll.

Snooty Sally’s storylines have tended towards the comedic in recent years, making her Weatherfield’s 21st century answer to social climbing Annie Walker, but this latest development is a dark chapter in how Sal’s public profile as a councillor has serious consequences for her private life. For actress Sally Dynevor, it’s a topic she applauds the show for tackling.

“Sally has been trolled online and finds it difficult, but at first she thinks she can deal with it. She feels like this must happen to anybody in such a public position and Sally has always wanted that kind of profile. But when it gets darker, she just wants to throw the towel in.”

In next Friday’s episode, Sally receives a call from the hospital, and has no reason to suspect it isn’t genuine. However, when she is told the shocking news that her latest mammogram has shown the cancer has returned, Sally is stopped in her tracks.

“Sally is really shocked,” continues Dynevor, who battled breast cancer in real life at the same time as her alter ego in 2009. “It was the last thing she expected. She thought everything was okay after her last check-up so it is very frightening for her that now they want to see her and there may be a problem.”

Delivering the bombshell to husband Tim that she has to go into hospital as her illness could be back, the couple share an emotional scene as they nervously contemplate an uncertain future… But then Rosie and Sophie burst in and play a recording of Sally’s phone call from the hospital that has been posted online – which is when it becomes clear the whole thing has been a vicious prank.

She just can’t believe that anyone would do something so horrific and feel so strongly about her to cause so much pain and worry,” explains Dynevor. “It is the worst thing anyone could do.”

Tim is furious to learn his wife had been dealing with her internet abuser on her own before it took this disturbing turn, and insists she deletes all her accounts. Disturbed Sally, meanwhile, struggles to move on from the upsetting incident.

“She just wants to give it all up, and doesn’t even want to leave the house. Sally has lost her confidence and really feels like a victim.

This is such an important issue to tackle as it goes on all the time, especially young people with mobile phones. I’ll admit I have found it hard as it is a difficult subject, but it is essential that we tell this story.”

Thankfully there are some lighter moments interspersed with the drama in next week’s episodes, as Sally’s daughter Rosie contemplates a return to glamour modelling to get Kevin out of debt, and there’s a thaw in the frosty rivalry with arch enemy Jenny Bradley.

“Both Sally Metcalfe and Sally Dynevor are thrilled that Helen Flanagan/Rosie Webster is back! She is an absolute treasure and I love working with her. For Sally it is fantastic because Rosie is the most wonderful daughter and she has always been very protective over her.

“As for Sally Anne Matthews (who plays Jenny) we have known each other for years and have a lot of fun doing scenes together. She has a brilliant memory and reminds me of things we got up to when we were younger!”

Sally and Jenny stop arguing for five minutes when they join forces to promote Jenny’s mastectomy bra business venture on local radio, with Sal sharing her own experiences of her brave fight against cancer. Does this mean Sally and Jenny have called a ceasefire?

“In a way I’d like their new-found friendship to continue but then again it’s quite nice playing rivals too! It is nice to have a bit of both, when they like each other one minute and hate each other the next…”

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