The pair have agreed to give a performance of their duet 'Another Way to Die', which is being used as the theme for forthcoming 007 movie Quantum of Solace.
Meanwhile, the show's finalists will be asked to belt out other Bond theme tunes, including Madonna's 'Die Another Day' and Shirley Bassey's 'Goldfinger'.
An insider told The Sun: "It's going to be brilliant. All the judges can wear black tie and we'll have a live orchestra. There are some great songs for the finalists to choose from.
"Everyone is excited about it. Let's face it, Simon would make an ideal Blofeld, Cheryl would be perfect as Pussy Galore, Dannii could be Vesper Lynd - and of course Louis would be Miss Moneypenny."
The X Factor continues at 7.10pm on Saturday on ITV1.