Mal, Evie, Jay and Carlos may have once been the baddest of the bad, but their wicked ways are (mostly) behind them-and now graduation is almost here! But Auradon's biggest threat is still at large... trapped on the other side of the barrier, Uma is more desperate than ever to get her long-awaited revenge against Mal. Mal and Uma have a score to settle, and they'll come face to face in an explosive underwater battle that could determine the fates of Auradon and the Isle of the Lost once and for all.