Whoops, there it is: that whacky left-wing liberal agenda to turn our planet into a garden paradise. The deliberate environmental consciousness-raising underlying The Last Mimzy will probably turn off some folks, the ones who are perfectly fine with breathing pollutants and ingesting hormones in cows’ milk, the ones who don’t mind that the oceans are dying and the ice caps are melting. But the rest of us will be very glad some day that their kids may be starting to get the message.

And this is a charming vehicle for that message -- based on a classic 1940s-era science fiction short story by Lewis Padgett (a pseudonym for the husband-and-wife team of Henry Kuttner and C.L. Moore), this is a cozily old-fashioned story about the fears and marvels of childhood, about family love, and yes, about a stewardship for our environment that is not easily dismissed as New Agey -- though as the man said, what’s so funny ’bout peace, love, and understanding? -- but more squarely in the realm of mature, sensible responsibility.

It comes down to the oddly clearheaded logic of children. When ten-year-old Noah (Chris O’Neil) and his kindergartener sister, Emma (Rhiannon Leigh Wryn), discover strange artifacts in their yard, of course they keep these mysterious toylike things a secret: Mom would take them away if she knew about them. Cuz they’re weird: they glow funny, or hover in a way that defies gravity, or disassemble your flesh on a molecular level when you stick your hand in them. Also, the adorable stuffed bunny that comes out of one of them can talk, but only to Emma, and it Knows Things. The toys are all way too cool, but Mom wouldn’t get it. So they stay a secret.

For now. Eventually Noah’s science teacher (Rainn Wilson: Sahara) sees that something weird is going on with the kid, and he comes to talk to Mom (Joely Richardson: The Affair of the Necklace, The Patriot), who has also started to notice her boy ain’t right, and things go from weird to worst. The toys -- which are, as you may have guessed, the scientifically advanced products of distant centuries sent back in time on a mission -- turn out to be way more dangerous to play with than the kids expected. Homeland Security gets involved, natch, bringing a decidedly modern level of paranoia to a story that also consciously evokes the creepy allure of Alice in Wonderland -- there’s danger here, which all good and truly effective stories for children need. It’s okay to be a little scared -- some things are worth being scared about. And some things that seem scary at first are the ones that teach us how to figure out what’s genuinely scary, and what isn’t.

Much rests on the child actors here -- The Last Mimzy wouldn’t work if we didn’t believe in them. And we do: they create a beautifully realistic sibling relationship -- mostly adoring each other, and fighting just a bit -- but even more importantly, they evince a willingness to be open to all possibilities is utterly enchanting, and a terrific reminder to us stick-in-the-mud grownups to keep an open mind. Not so open that our brains fall out... open just enough to let our imaginations out to play once in a while.

(Technorati tags: Last Mimzy)