Pic: ITV/Ken Mackay/Rex Features
The X Factor semi-final night will see the four remaining acts perform two songs each. The show's theme is Michael Jackson and tomorrow night's results show will feature a guest appearance by the late singer's sister, Janet Jackson.
Each contestant will sing one song from Michael Jackson's extensive back catalogue. The Jackson tracks have been selected by their mentors.
Mentor Dannii Minogue has chosen the 1987 Michael Jackson track The Way You Make Me Feel for the last remaining girl in the contest, Stacey Solomon. Cheryl Cole has selected She's Out of My Life from Jackson's Off The Wall album for her final boy, Joe McElderry.
Simon Cowell, the only mentor with two acts still in the contest, has chosen Man in the Mirror from the album Bad for Danyl Johnson. For Olly Murs, Cowell has selected Can You Feel It - not in fact a solo track, but one performed by The Jacksons in 1980.
Each contestant's second song has been chosen by themselves. Their brief was to choose something to win enough public support to get them through to the final.
Stacey Solomon has selected Somewhere from Leonard Bernstein and Stephen Sondheim's classic musical West Side Story as her 'song to get through to the final'. The same song took Rhydian Roberts all the way to the final in the 2007 series - will it be as lucky for the girl from Dagenham?
Joe McElderry will perform Open Arms a 1982 hit for American rockers, Journey. He received rave reviews for his version of Journey's Don't Stop Believin' in week four, so this could be a crowd-pleaser.
Danyl Johnson has chosen I Have Nothing by Whitney Houston from the film The Bodyguard. During Divas week, Danyl performed a new Whitney track, I Didn't Know My Own Strength. This one should give him a chance to do what he does best - belt out big notes.
Olly Murs will sing Stevie Wonder's version of the Beatles' hit We Can Work It Out. Olly has previous form with Stevie Wonder songs - his version of Superstition during his first audition saw him fly through to bootcamp.
The semi-final is on STV tonight at 8pm and will be available for 30 days on the STV Player.
