Emmerdale's Faith Dingle is to discover her breast cancer has returned.
Sally Dexter's character will be told the devastating news in episodes due to transmit later this week, and the 62-year-old star feels a "real responsibility" to tell the hard-hitting plot.
She said: "It's upsetting, but really important as a storyline, because it's more than a storyline for so many people.
"It matters to people who are going through it as well as people who will go through it. I feel a sense of real responsibility, but also a privilege to be doing this storyline."
The upcoming 'Emmerdale' episodes have been produced with the support of charity Breast Cancer Now to give Faith's secondary cancer storyline a realistic and authentic depiction.
Catherine Priestley, Clinical Nurse Specialist at Breast Cancer Now, said: "With it estimated that around 35,000 people are living with secondary breast cancer in the UK, it's been an incredibly important opportunity for us to provide expert guidance around Faith's storyline - giving a steer to script writers as to how her diagnosis and experience of the disease can be portrayed accurately and raising awareness of some of the signs and symptoms of secondary breast cancer among millions of 'Emmerdale' fans.
"Everyone's experience of breast cancer is different, but we know from calls to our Helpline just how anxious women may feel about the possibility of their cancer returning, and how overwhelming the impact of a secondary breast cancer diagnosis can be for patients and their families."
Faith will turn to Moira (Natalie J Robb) for support as tensions remain high with her children, Chas (Lucy Pargeter) and Cain (Jeff Hordley), who she's unable to talk to about her diagnosis.
Emmerdale Producer, Laura Shaw, added: "Faith's devastating cancer diagnosis will impact not only her life, but all those around her. We know at the very core of the Dingles is a strong sense of family and love, so for them to try and navigate through this heart-breaking time will be incredibly difficult.
"Faith's zest for life with her spicy sense of humour and appetite for fun and adventure means that while there will inevitably be some painful and heart wrenching moments, we will also see life affirming and positive moments of light in the story too.
"Given the calibre of actor Sally is, I know she will approach the story with great honesty and depth and do it justice and this in turn will raise awareness of such an important issue that affects many people on a daily basis."
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