HORROR in Emmerdale tonight as THIS character is delivered a LIFE-THREATENING bombshell

Emmerdale's Lydia Hart is in for a surprise tonight when the mum she believed was dead turns up at the Dingles' house... and she's got news.

Tonight’s Emmerdale sees Lydia Hart get the shock of her life when she comes face-to-face with the mum she hasn’t seen since she was a child.

But it’s not just the fact she is seeing her biological mother for the first time in decades that will leave Lydia stunned… she also believed her mum was dead after her long-lost sister Beth told her last week she’d died, and her mum is about to drop a bombshell.

Emmerdale fans have seen Lydia’s life turned upside down over recent weeks, and it all started when she was given a huge sum of money from a mystery benefactor.

Mandy tries to help Lydia in Emmerdale

Lydia was shocked when she was given a huge amount of money recently (Picture: ITV)

Lydia was determined to find out who would deposit so much money in her account, and after some digging by Mandy Dingle, it was discovered that Agatha Finn, Lydia’s mum, was the one who left her the cash.

But when Lydia went to track down her family, she was coldly told by her sister Beth that both their parents were dead.

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However tonight’s Emmerdale (7pm, see our TV guide for full listings) sees a huge twist in the tale when Mandy does yet more detective work and discovers that Agatha isn’t dead at all, and in fact alive, well, and desperate to see the daughter she was forced to put into care all those years ago.

Tonight’s episode sees Mandy bring Agatha to Emmerdale, and Lydia is shocked when she is reunited with her mum.

Emmerdale, Lydia Hart, Sam Dingle

Lydia comes face-ti-face with her mum in tonight’s Emmerdale (Picture: ITV)

As she prepares to face up to her past, Lydia is happy when the pair talk about old times.

However, her happiness soon turns to horror when Agatha drops a huge bombshell on her daughter that will change her life forever.

Agatha reveals that Lydia’s dad died of Huntington’s Disease, and with it being hereditary, there is a likely chance that Lydia could have the same thing.

Emmerdale, Lydia Hart, Sam Dingle

After discovering the truth about her dad, will Lydia decide to get tested for Huntington’s disease? (Picture: ITV)

How will Lydia take the news? And where does this leave her new-found relationship with her long-lost mum?

Emmerdale airs weeknights at 7pm on ITV, with an extra episode at 8pm on Thursdays.