Simon Cowell told this year's crop of Britain's Got Talent hopefuls they had "everything to play for" as the first live semi-final got under way.
With the audition stage over, 40 acts have been picked to join the five Golden Buzzer contestants in the live rounds of the show.
Nine acts took to the stage on Sunday in a bid to secure one of the slots in the grand final.
Richard Bayton was the first to go, and he entertained the judges with a medley of tracks that had judge David Walliams on his feet.
"Send everyone else home, we've found our winner," he said.
Amanda Holden joked it was time for Simon to propose to his partner Lauren Silverman after they watched gymnastics group Spartan Resurrection perform.
Discussing whether the end of the routine had been big enough, Simon pointed out to Amanda that it had contained a proposal.
"I know, even bigger than that Simon, bigger than a proposal... which would be good for someone like you to do," she said.
As the audience laughed and whistled, David suggested Simon pop the question on live TV.
He jokingly responded by asking David: "Will you marry me?"
Singer Kathleen Jenkins was on next and impressed all four judges with her rendition of One Day I'll Fly Away.
Amanda said: "You just were extraordinary and you really, really deserve this moment."
Simon added: "I have a feeling Britain is going to get behind you tonight."
A nervous-looking Alesha Dixon joined contestant Ben Blaque on stage for a game he called Crossbow Roulette.
Ben stood strapped to a wall and asked the judge to pull levers which fired arrows towards him.
"Oh, my heart is pounding," she said.
At one point Alesha accidentally let off two arrows at once, but thankfully missed Ben.
Warming up to her challenge, she said: "Do you know what? This is fun, I'm not going to lie."
There were calls for Simon to get up and show off his own moves after he said the ballroom routine performed by the Ystrad Fawr Dancers was "lazy".
However, the music mogul put his fingers in his ears and remained firmly in his seat.
Voiceover artist Darren Altman failed to win over Simon with a series of celebrity impressions set in a pretend restaurant.
Darren - who mimicked stars including Gordon Ramsay and Bear Grylls - looked crestfallen as Simon declared his performance had been "terrible".
Simon's fellow panellists assured him he was very talented and suggested that standing on stage doing impressions would have been enough.
Last to go was Alesha's Golden Buzzer Act, 100 Voices Of Gospel.
The singers received a standing ovation from Alesha, Amanda and David.
Simon said their performance was in "a different league" to anything else he had heard all night and said they should win the whole show.
The winner of the ITV show, now in its 10th year, will perform for the Queen at the Royal Variety Show and win a £250,000 prize.