The CBBC presenter is only the second contestant this series to get full marks and scored the earliest ever 40 in a series for the fast-paced Charleston.
But the effort of the routine was so much that Stephenson was left doubled over with dance partner Nancy Xu stuck on his back at the end of the dance and he then had to crawl away from the dancefloor on his stomach as he struggled to get back to his feet.
The judges agreed that Stephenson had found the style that suited him best as Motsi Mabuse told him: "This has to be the Charleston of the series."
— BBC Strictly ✨ (@bbcstrictly) November 13, 2021
Head judge Shirley Ballas added: "I just want to dance with Rhys side by side. I've never, ever seen a Charleston like that."
Anton Du Beke told him: "You absolutely smashed the place up, there's nothing left," while Craig Revel Horwood had one word for him: "A-ma-zing."
Stephenson was left in tears as he saw every judge give him full marks and told host Claudia Winkleman: "It had to be that one, it's the most CBBC dance out there."
Dancing just before Stephenson was BBC Breakfast presenter Dan Walker, who split opinion with his American Smooth with Nadiya Bychkova.
Revel Horwood told him it "totally lacked feeling" and had "no style", scoring it just four points, while the other judges told him it was his best dance yet and Du Beke gave it nine points.
Walker said: "I feel very passionately that dancing and this programme has got to be for people who've never danced before."
He added: "Nadiya taught me that when you smile people smile and they enjoy it and that's a whole new language I've learned this week."
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