When Rumpelstiltskin tries to take over Earth once and for all, The Avengers Grimm must track him down through time in order to defeat him.

When Rumpelstiltskin destroys the Magic Mirror and escapes to the modern world, the four princesses of "Once Upon a Time"-Cinderella, Sleeping Beauty, Snow White, and Rapunzel-are sucked through the portal too. Well-trained and endowed with magical powers, the four women must fight Rumpelstiltskin and his army of thralls before he enslaves everyone on Earth.