Hirokazu Koreeda is a director preoccupied with limbo. His After Life (1998) had a bunch of recently deceased souls trying to pick a single memory of earthly life they wanted to take with them to the next world. In Koreeda's Nobody Knows (inspired by true events, it's said), the twilight zone of choice is modern-day Tokyo, where a quartet of siblings, none older than 12, putters around a small apartment, waiting for a mother who may never return.
They're not even supposed to be there in the first place. Mama Keiko (the simply named You) has gotten around her landlords' rules by smuggling in three of her four kids in suitcases. Unable to send them to school, she instructs them to stay quiet and out of sight, and to make what progress they can on "homework" that she'll check when she returns at night from her job or from a date, or whatever else may happen to take precedence. Though girlishly good-natured and thus uniformly adored by her brood Keiko is a washout as a single parent, prone to unannounced absences that are only slightly ameliorated by her habit of leaving the kids a few thousand yen to play with while she's gone. As those absences get longer and more mysterious, oldest son Akira (Yagira Yûya) begins to recognize the massive responsibility that's been placed on his shoulders to look after his kin not that he has the training or the tools to wield that responsibility properly.
It's Where the Lilies Bloom meets Lord of the Flies, a harrowing cautionary tale that shows what can happen when children are left to fend for themselves and anarchy inevitably sets in. These four don't need The Cat in the Hat to mess up their lives and their living space; just remove all adult supervision for a month or so at a time and watch chaos take root.
Koreeda's precise rendering of that transformation is an exercise in gradualness. (He reportedly shot the film in sequence over the course of an entire year.) His eye for detail reveals the subtle signs of atrophy like bedding that eventually gets hauled out into the living room, the better to facilitate a schedule of lounging in front of the tube 24/7. More overt is the kids' abandonment of personal hygiene, resulting in a filthy, street-urchin look that's in shocking juxtaposition to the neighbor kids' fresh-scrubbed respectability. In Akira's house, we can see the social fabric unraveling before our eyes.
But does it have to unravel so slowly? At two hours and 21 minutes, the movie indulges somber sincerity at the expense of practicality. There's no need for a story this intimate to rival a Lord of the Rings installment in terms of time investment; a certain portion of the kids' prolonged heel-cooling could be truncated without sacrificing any of the film's impact, or its ultimate arrival at a climax whose inconclusiveness seems even more pronounced for being so delayed. Nobody Knows has a sweetly mournful feel, and it's well-performed throughout; still, it's a long time to spend in limbo.