‘DWTS’ Season 21 Partners Switch: What Couple Earned a Perfect Score?

Dancing With The Stars is spicing things up this week by changing partners for its celebrity contestants. Tom Bergeron reclaimed his spot as host after having off last week to tend a family matter and professional dancer Maksim Chmerkovskiy stood in as a guest judge. Monday night's Week 5 episode and new batch of dance couples resulted in Season 21's first perfect score.

Spy Kids star Alexa PenaVega entered the ballroom with her partner for the evening Derek Hough (her Season 21 partner is Mark Ballas). The duo accompanied by the DWTS professional troupe, tangoed their way to a perfect score with a stylish and well-executed routine. Alexa and Derek impressed the audience and received a standing ovation that included high praises from DWTS judge Carrie Ann Inaba.

Alexa's husband and Big Time Rush singer Carlos PenaVega also rose in the rankings this week with his partner Lindsay Arnold (his regular partner is Witney Carson) and landed just one point shy of his wife's perfect performance. Bindi Irwin also improved with the help of a partner switch (from Derek Hough) and danced with Val Chmerkovskiy; earning a 37-point score with a sensational cha-cha routine.

Missing from the ballroom are former contestants Garey Busey, Real Housewives of Atlanta co-star Kim Zolciak Biermann, Triple Crown-winning jockey Victor Espinoza and iconic singer Chaka Khan.

This season's remaining celebrity contestants include: Alexa PenaVega and her husband Carlos PenaVega, Paris train hero Alek Skarlatos, celebrity chef Paula Deen, Bindi Irwin, daughter of the late wildlife TV star Steve Irwin, singer Andy Grammar, social media star Hayes Grier, former Backstreet Boy Nick Carter and TV host Tamar Braxton.

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