Tasha Robinson’s review published on Letterboxd:
The comparison between this Pixar film's basic concept — a look inside an 11-year-old girl's head, where her emotions push for dominance — and the 1980s sitcom Herman's Head has been made many times. But it's not the concept, it's what Pixar vet and Up director Pete Docter and his team do with it. This is a speedy, often hilariously funny action-adventure, but it's also a mighty empathetic, sweet attempt to understand what sadness means, and why it's an important part of life, and how emotions interact with behavior. It's a smart film, and sometimes a tear-jerkingly emotional one, and it's so much better than the trailers suggest.