Brad Bird is back with a new animated film, and critics are mostly cheering.

"Ray Gunn" is a retro-futurist detective story set in a city of the future with flying cars, jetpacks and hologram billboards. The Guardian gave it a glowing review, calling it "an old-school family classic." Critic Peter Bradshaw called Bird "the Spielberg of animation."

Bradshaw said the film rescues the genre from "dull, AI-formulaic stories and visuals." He called it "smart, witty, humane," with "amazing cityscape design" and a sweet romance. The city has hints of the classic films "Metropolis" and "Blade Runner."

Variety called it "a giddy retro-futurist noir" with plenty of energy. But its critic noted the film's future is not all that new. In the movie, humans live alongside aliens but have fallen back on old habits of prejudice. Crime and corruption still run wild, and pop-up ads appear as holograms in your personal space. "Still, at least the future looks good," Variety wrote.

GeekTyrant's reviewer said he went in with "ridiculously high expectations" and called it "wildly entertaining," packed with style, humor and heart.

"Ray Gunn" is Bird's fifth animated feature, Variety said. His earlier films include "The Iron Giant," "The Incredibles," "Ratatouille" and "Incredibles 2." He has won two Academy Awards for best animated feature.

Film noir is a style of crime drama known for dark streets, tough detectives and moral gray areas. Bird mixes it with bright, family-friendly science fiction. Critics say the result should please both children and the adults who grew up on his earlier films.

What we know: early reviews of 'Ray Gunn' are largely positive.
What we don't: how it will do with audiences.