The 23-year-old singer – nominated for four awards at the prestigious music ceremony including solo artist of the year and song of the year – took to the stage at the star-studded ceremony early on with a performance of his hit Someone You Loved.
Capaldi confessed on the red carpet: “I hate performing on TV. I get very, very, very nervous. You just try to get through it as quick you can.
“We’ll see how it goes - there’s two big notes in the middle of that song. I’ve made a big old rod for my own back there.”
Also set to perform at the awards are Sir Rod Stewart, 75, who walked the red carpet with his wife Penny Lancaster and Faces bandmates Ronnie Wood and Kenney Jones.
JLS stars Aston Merrygold, Oritsé Williams, Marvin Humes and JB Gill – who found fame on The X Factor – attended the ceremony to celebrate their reunion and were greeted warmly by the grime star as they crossed paths on the red carpet.
Model Adwoa Aboah admitted she got changed in the car on the way to the ceremony.
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She said: “I was a bit nervous. I had to get changed in the car because this dress creases really easily. So I came in a tracksuit and then got changed in the car.”
Also performing at the ceremony are Harry Styles, Lizzo and Billie Eilish.