Last night saw the remaining eight X Factor finalists perform live for the sixth time, singing songs with a Best of British theme.
This evening, Dermot O'Leary revealed that District3 and Union J had received the fewest public votes and would have to sing again.
It was the second time for both groups in the bottom two.
In the sing off the pair will go head to head and the judges - Gary Barlow, Tulisa Contostavlos, Nicole Scherzinger and Louis Walsh - will decide which of the pair stays and goes.
Although if the first five weeks are anything to go by, they'll just send it to deadlock!
Find out soon!
The X Factor 2012 continues next Saturday and Sunday on ITV1 and ITV1HD.