From the creators of Ice Age and Rio comes this ecotastic fairytale about nature's balance, bucolic renewal and, er, tiny green warriors called "leafmen".
Sensitive teen MK (voiced by Amanda Seyfried) returns to the family home, still grieving over the loss of her mother and unable to connect with her professor father or his crackpot theories about little people who live in the forest.
Before you can say "Gulliver", she's been shrunk to leafman-size and enlisted in their great conflict with the Boggans, the opposing forces of decay and destruction.
The idea of a human encountering an alien forest race brings Avatar to mind, and little design echoes reinforce the association. (Warrior Ronin, all crewcut and cheekbones, is surely modelled on Sam Worthington.)
There's distinctive voicework from Colin Farrell, Beyoncé Knowles, Christoph Waltz and, as a comedy snail, Chris O'Dowd, who gets a very good line about a fruit fly.
Five writers collaborated on the screenplay, which may explain both the occasional comic bull's-eye and its air of calculation – no "green" message has been allowed to go uncapitalised.