The actress, who was second from bottom on the leaderboard, landed in the dance-off with her partner Johannes Radebe following their fireman-themed Cha Cha to Fontella Bass' Rescue Me.
Caroline was joined by EastEnders star Maisie Smith and Gorka Marquez, which was a surprise as the pair had impressed judges with a Salsa to Better When I’m Dancing by Meghan Trainor.
DJ Clara Amfo, meanwhile, had the lowest score on Saturday but was saved by the viewers' vote.
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After both couples in the dance-off performed again, the judges gave their verdicts. Craig Revel Horwood chose to save Maisie and Gorka.
He said: "I absolutely love both couples, but for me, one couple was outstanding and danced as though their lives depended on it and that couple I would like to save, Maisie and Gorka."
Temporary judge Anton Du Beke agreed, saying: "Well I thought both couples danced beautifully. "I think they are beautiful couples [and] danced fabulous routines.
Caroline bid a fond farewell to the BBC show
"One couple was a bit cleaner than the other couple, there was a couple of mistakes in there. So the couple I would like to save are Maisie and Gorka."
Head judge Shirley Ballas said she would also have chosen to save Maisie and Gorka.
After the decision, the show's co-host Tess Daly asked Caroline if Strictly had allowed her to fulfil her childhood dream of becoming a dancer.
Caroline replied: "Yeah, in a way slightly more than that because I have had the honour and privilege of working with some of the greatest dancers this country has ever known.
Maisie Smith was in the dance-off for the second week running
"I mean, I really believe it, I think they are absolutely fantastic. But of course, my greatest gift coming on this show is this man."
Johannes also gushed about his partner, saying: "Oh my gosh, what a woman, thank you, thank you again, thank you, thank you, thank you.
"I don’t know what to say, because it was a beautiful one, I had a beautiful journey with you, thank you my darling, thank you."
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