The Scottish teenager will perform the Westlife smash 'Flying Without Wings' alongside Shane in an attempt to take home the X Factor 2013 crown.
Of course, Nicholas and Shane have met before as Shane joined Nicholas' mentor Louis Walsh at judges' houses earlier in the series, where Nicholas won his place at the live shows.
Speaking on ITV's Daybreak, he said: "People think Shane is only doing it because of Louis and Westlife but I wanted Shane to do it because Shane believed in me since judges' houses and he's one of the ones that strongly felt that I should have gone through. He understands where I'm coming from."
Shane spoke about his belief in Nicholas in an interview with the Daily Record in October, saying: "(Louis has) got three really good guys in (his final three) but Louis was saying when he was watching the videos back, Nicholas was standing out.
"He was saying, 'I'm telling you, watch this guy, I'm telling you, watch him'. I know when Louis talks like that, he really means it. Scotland will be behind him 100 per cent and I think he's got a great story, he's got a great voice, he's got a great talent, he's a nice kid and people are going to relate to that."
In addition to singing with Shane, Nicholas will perform two other tracks: 'Angel' by Sarah McLachlan and 'Candy' by Robbie Williams.
He faces competition from Luke Friend and Sam Bailey.
The X Factor 2013 final kicks off Saturday night (14 December) on ITV and concludes the following evening.