Welsh choir Cor Glanaethwy won the public vote of Britain’s Got Talent’s first semi final with a rousing performance of Celine Dion and Andrea Bocelli’s hit The Prayer.

“It was powerful, emotional. Wales right now will be bursting with pride after that,” Simon Cowell said.

“You made my heart burst,” added Amanda Holden. “That’s one of the most beautiful pieces of music I have ever heard. I honestly think you could win the entire series.”

“I was sitting here with tears in my eyes,” said David Walliams. “That really was world-class.”

“You are superb,” Alesha Dixon agreed.

The judges then had to choose between Alesha’s Golden Buzzer act, dance group Entity Allstars, and12-year-old singer Henry Gallagher, voting three to one for Entity Allstars.

“I’m so proud of you,” Alesha told the dancers, who performed a Harry Potter-themed routine – with an unscripted stumble at the end.

But perhaps the biggest excitement of the night was the new Guinness World Record set by Cally the Wonderdog, popping 100 balloons in 41.67 seconds and beating the current record of 44.9 seconds held by an American dog called Anastasia for 10 years.

Cally had failed at the record attempt in her audition but definitely made the most of her second chance.

“And if Cally makes it to the final, the daughter of Anastasia will come from America to compete against her.”

Well, that match is off.

David’s Golden Buzzer act, Lorraine Brown, failed to win over the voters and Simon buzzed her, but the other judges let her finish her quite bizarre routine, singing a song about living in space.

“Simon’s just jealous that I have the winning act,” David told Lorraine.

Er, no you don’t, David.

But what the judges really didn’t like was impressionist Andrew Fleming.

Alesha and Amanda buzzed him but Simon and David let him finish his act…then delivered the bad news…

“That was not as good as the first time,” Simon told him.

“Sorry, I know it’s not easy but I wasn’t belly laughing,” Alesha told Andrew. “I thought your act was dated.”

“Same here,” Amanda said. “I just don’t think you’ve got it.”

Also trying for – but failing to win – a place in the final were singer Becky O’Brien, Ruby Red Performers, and roller-skating brother and sister Billy and Emily England.

Britain’s Got Talent Live Semi-Finals continue on ITV, Tuesday, May 26, 7.30pm.