BBC Michael McIntyre's Big Show viewers in tears as unexpected guest blows them away

They said they couldn't tell who was the professional singer as LeAnn Rimes joined her on stage

Michael McIntyre's Big Show viewers were left in tears over an incredible performance from the unexpected guest of the show. Each week the comedian surprises a member of the public by getting them to sing live at the end of the BBC programme.

Sarah thought she was attending a country night, but she burst into tears as the wall fell down while she was riding a mechanical to reveal the studio audience cheering. Michael explained that Sarah had been through an 'incredibly terrifying' experience after being diagnosed with a brain tumour.

He revealed the mum had to learn how to speak again and had suffered from seizures since her operation. She explained: "I had my gorgeous little girl and then eight weeks after I had a fall at home. It was a brain tumour...it was the size of a satsuma."

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Sarah's entrance to the show was surprising, but she said she thought something strange was happening. She told Michael: "I knew something weird was going on. It smelt of MDF in there."

Her phone then started ringing and she revealed it was her 'alarm for drugs'. Michael told her to take her medicine, which she revealed was for epilepsy, before continuing with the show. Sarah was nominated by her husband Tom after dad because she loves singing. And she surprised again when she was joined by one of her musical favourites LeAnn Rimes as she sang her hit How Do I Live.

After the performance, Sarah said: "It feels like a dream...you know when you have a really good dream and you never want to wake up? So thank you." LeAnn added: "I was backstage bawling...your story is beautiful."

Viewers were left in tears by the performance. One wrote: "#BigShow can't really tell which is the professional singer!" Another agreed: "Blimey, she's good."

A third admitted: "Oh, God. I’m crying here." And a fourth echoed: "I'm bawling again Michael!!!"