To save themselves the agony of having to kick off one of their own acts, judges often taken it to deadlock and leave the decision up to the public vote... but NOT Louis tonight!
He chose to save controversial Kitty over 'cruise ship' Sami (Gary Barlow's words, not ours), and the audience let rip with boos when Louis took to the stage to commiserate Sami, who got the heave-ho.
It was Kitty's rendition of Lady Gaga's 'Edge of Glory' which won the day over Sami's version of Aretha Franklin's 'Natural Woman' in the sing off on Sunday.
[See also: X Factor week three: our verdict]
[See also: Misha B accused of bullying X Factor acts]
Twitter was buzzing with angry comments over the decision, and a lot of viewers wanted to see Frankie Cocozza at the bottom of the pile again.
Many were predicting Sami would be in the danger zone after her outdated performance of 'Turn Back Time' on Saturday night, which Gary called "boring" and "karaoke."
Although Kitty cranks up those column inches and gets many viewers' backs up, her name wasn't in the mix in most online (and pub) discussions about who would be singing for their X Factor lives.
Her fire-filled performance of 'Live And Let Die' had its fair share of bum notes, but at least she got us to sit up and pay attention, which was an achievement in itself after several dull songs on Saturday.
We feared Sophie Habibis would wind up in the sing off, but she survived to croon another week *phew*
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Louis managed to take over the show and we all know he loves the attention, so although he's lost an act he's certainly gained more exposure.
He could have ducked out of choosing who to send home, as Gary and Kelly Rowland saved Kitty while Tulisa Contostavlos saved Sami, but he went with his gut and gave Kitty a third vote of confidence.
Earlier in the evening Louis took the opportunity to grab the limelight when he apologised to Misha B for calling her a bully on Saturday's show. Tulisa didn't follow suit. Interesting.
So Kitty makes it to Halloween week, which is fitting. We're imagining the outfit already...
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