The five ninja friends have escaped the Overlord and are on the run. Now they must rescue Sensei Wu, shut down the Overlord's power, and do a system reboot.
Under the tutelage of Sensei Wu, the "chosen four" ninjas Kai, Jay, Cole, and Zane must use their elemental powers to defeat Sensei Wu's evil brother, Garmadon, and Samukai's army of skeleton warriors before Garmadon can conquer the world.
When Cole, Jay, Kai, and Zane visit the high-tech New Ninjago City they meet the super-genius Cyrus Borg, who warns them about the impending war with the Nindroids.
Zane, a member of Sensei Wu's team of ninja warriors who has no memories, wants to find answers about his past, but getting them might put the whole team in danger.