Based on the children novel Here be Monsters by Alan Snow, the story is about a young orphaned boy named Eggs raised by underground cave-dwelling trash collectors who tries to save his friends from an evil exterminator, the towns villain, Archibald Snatcher. When Snatcher comes up with a plot to get rid of the Boxtrolls. Eggs decides to venture above ground and into the light, where he meets and teams up with fabulously feisty Winnie. Together, they devise a daring plan to save The BoxTrolls family.