Lisa and Zak will be seen arriving back to a welcome home party organised by daughter Belle. But when Belle later spots Lisa getting teary-eyed, it isn't long before the truth about her illness comes out.
Find out more about amyloidosis, the condition Lisa is suffering from, below.
What is amyloidosis?
The Dingle family matriarch has a rare condition called amyloidosis, which is causing heart failure thanks to a build-up of abnormal proteins in her body. Chemotherapy that Lisa has been receiving while away in Scotland hasn't worked, all of which means that she now has just months left to live.
On the issue of how amyloidosis can cause heart failure, the NHS website states: "Deposits of amyloid in the heart can cause the muscles to become stiffer, making it more difficult to pump blood around the body."
Why is Belle annoyed with Charity?
Belle will be seen lashing out at Charity after she discovers that the Woolpack landlady has known for some time that Lisa is terminally ill. Viewers will recall that, during Emmerdale's all-female International Women's Day episode shown on Friday 8 March, Charity made a secret trip to see Lisa.
In a poignant scene, the pair discussed arrangements for Lisa's funeral, while Charity agreed to honour Lisa's wish that her diagnosis should be kept a secret from the rest of the Dingles for the time being.
Is Jane Cox leaving Emmerdale?
Following the broadcast of the all-female episode, Cox announced that she would be exiting after 23 years, though the ITV soap has yet to reveal when Lisa's final episode will be shown.
Speaking about her departure, the actress said: “Lisa is so close to my heart and has been a huge part of my life all these years. I will shed more than a few tears when it comes to filming her final scenes, but I’m looking forward to returning to the show to give the character a deserving farewell. I will miss her.”
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