The X Factor judges Simon Cowell, Nicole Scherzinger, Sharon Osbourne and Louis Walsh spotted filming ‘secret boot camp’

THE X Factor filming is well and truly underway, as yesterday the judges were spotted leaving a top secret bootcamp in North London.

The familiar faces of Simon Cowell, Nicole Scherzinger, Sharon Osbourne and Louis Walsh were seen outside the undisclosed location after a long night of work.

Despite the late hours relations between the four judges all seemed to be still going well, and old friends Sharon and Louis, both 63, were pictured sharing an embrace and a car home together.

While Nicole, 38, who was wearing a red halter neck crop top and fitted white skirt beamed as she was pictured entering her ride home.

With the exception of Nicole, 38, this year sees the original judging line-up heading up the iconic talent show.

Nicole was part of the panel in 2012 and 2013, and makes a return this year after being popular with audiences and coaching season nine winner James Arthur.

Cameras also caught a glimpse of the young hopefuls all hoping to be shot to One Direction levels of mega stardom.

Simon is the only man standing after a mass exodus of last year’s line-up, that saw Rita Ora, Nick Grimshaw and Cheryl Cole quit as judges, plus Olly Murs and Caroline Flack being replaced by X Factor veteran Dermot O’Leary ,  and now the mogul says he's giving audiences what they want.

He told The Mirror: “The fans didn't like last year's panel, you can't ignore them.

“I like reunions and I like the idea of what I call ‘The best of The X Factor.’”