Fletcher and Dowden went up against Rhys Stephenson and Nancy Xu in the dance off, but judges Motsi Mabuse, Anton Du Beke and guest judge Cynthia Erivo chose to keep CBBC presenter Stephenson - although head judge Shirley Ballas admitted she would have saved Fletcher instead.
Read more: Strictly musicals week's best ever moments
McFly singer Fletcher leaves the show in his favourite themed week, after dedicating his Les Miserables-themed couple's choice routine to his sister Carrie, a West End star.
— BBC Strictly ✨ (@bbcstrictly) November 21, 2021
Du Beke told the bottom two couples that they had performed "an outstanding dance off", but chose Stephenson's Jive inspired by Footloose as the better performance.
Mabuse told them: "I think this was so tough, I mean the toughest I have seen since I've been here."
Fletcher, who had said his aim was to get to musicals week as musical theatre meant so much to his family and he had started performing in shows himself from the age of eight, said: "I’ve made the best friend in Amy, you’ve been amazing, thank you so much for teaching me how to dance, I know it was a struggle at times."
He said of his three young sons: "I hope they are proud. They’ve loved learning to dance. That’s the thing, Amy hasn’t just taught me, she’s taught my kids."
She said: "Who gets to say they got to go on tour with McFly? Tom has given his all, and he is so humble, so genuine, so talented.
"The whole Fletcher family, they welcomed me in with open arms and honestly I couldn’t have wished for a better time. These memories are going to live with me for the rest of my life, and I’m telling you this now, the Fletchers are not getting rid of Amy."
Fletcher had finished musicals week's live show joint bottom of the leaderboard with Dan Walker, who once again avoided the dance off thanks to the public vote.
Meanwhile, Tilly Ramsay, who had been in the dance off for the last two weeks running, turned her fortunes around by topping the leaderboard with a perfect score of 40 for her Matilda-themed couple's choice.
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