The top four acts compete for the title of Best in the World and the $1 million prize for judges Jennifer Lopez, Derek Hough and NE-YO. Les Twins, Kinjaz and Keone & Mari guest star.

Ciara mentors top-scoring dancers, who perform for Jennifer Lopez, Derek Hough, NE-YO and guest judge Misty Copeland to win their division and move on to compete in the World Final.

Mel B joins NE-YO to mentor the Junior Division, while Paula Abdul and Jenna Dewan mentor the Upper Team Division as the divisions are cut to three.

Savion Glover joins Jennifer Lopez to mentor the Junior Team Division, while Julianne and Derek Hough mentor the Upper Division as the divisions are cut to three.

On the final night of The Duels, the top qualifying acts choose a rival for a head-to-head battle; only one can move on to the next round, cutting the field of competitors in half.

On the third night of The Duels, the top qualifying acts choose a rival for a head-to-head battle; only one can move on to the next round, cutting the field of competitors in half.