Ant and Dec were fuming when Britain's Got Talent auditions were held up because Simon Cowell was having a bath.
The presenting duo, along with judges David Walliams and Alesha Dixon, arrived at the Cardiff leg of the auditions on time at 2pm but at 4pm were still waiting for the 52-year-old media mogul.
Dec wrote on twitter: "If you're outside in the Q in Cardiff, tweet @SimonCowell and tell him to hurry up. (sic)"
A source told the Sun: "Simon's a law unto himself. He never gets up before noon and is happy working late at night.
"The problem is the thousands of people who turned up for the show - as well as Ant and Dec and his fellow judges David and Alesha - were on time. They had to sit twiddling their thumbs for a couple of hours while he pampered himself in his suite."
The X Factor boss is believed to have further angered the Geordie duo when he hopped in the bath tub in the middle of the auditions.
The source added: "It's not uncommon for Simon to get up and go for a bath during the show. He comes back smelling really lemony."
Meanwhile, Cowell has hired Sharon Mills - the producer of E4 reality show Made in Chelsea - to film backstage scenes in order to catch the bickering and flirting between the contestants.
A source told the Daily Star: "Out of all of Simon's shows, Britain's Got Talent has the most variety from animals to circus acts and fire-eaters.
"He wants to give viewers a bigger insight into what happens backstage with them all. With Sharon's track record in reality TV, she's perfect for the job. With such a wide range of people there's always lots going on - fireworks and tantrums and maybe even romance."