Cosmo, an affectless mob bookie who lives in the basement of a retirement home, is promoted to hitman. He learns his new trade from Steve, a seasoned killer. He falls in love with a yoga teacher, Jasmine, and must figure out a way to leave the mob so they can be together.

Queen Poppy and Branch make a surprising discovery — there are other Troll worlds beyond their own, and their distinct differences create big clashes between these various tribes. When a mysterious threat puts all of the Trolls across the land in danger, Poppy, Branch, and their band of friends must embark on an epic quest to create harmony among the feuding Trolls to unite them against certain doom.