There are sides of ourselves — reckless ones, ruthless ones, occasionally hopeless ones — that we never want our parents to see, even, or perhaps especially, in adulthood. What we rarely consider is the equal number of imperfect facets — incompetence, insecurity, simple loneliness — that our parents do their best to conceal from us. And so the hidden half-lives of a civilly estranged father and daughter overlap to uproarious and finally devastating effect in "Toni Erdmann,” a stunningly singular third feature by German writer-director Maren Ade that transports the intricately magnified human observation of her previous work to a rich, unexpected comic realm.

At 162 minutes, this episodic, slow-building study of reluctantly shared depression is baggy, yes, but necessarily so: The film takes precisely as much time as it needs for its muddled, maddeningly human characters, played with extraordinary courage and invention by Peter Simonischek and Sandra Hüller, to find their way into each other, and so into themselves. A writer as skilled and attentive to loaded details as Ade could likely have told a touching, redemptive tale of a harried businesswoman and her befuddled dad resolving their differences and finding common ground in half the running time, but “Toni Erdmann”  has many more things racing and sometimes reversing through its mind. Engrossing in its own right, that fragile father-daughter relationship becomes a prism through which Ade addresses a far broader spread of contemporary manners and mores — not least a tacitly blistering feminist evocation of the everyday setbacks faced by women in the workplace.

That Ade’s screenplay limbos through such potentially clashing levels of sentiment and subtext without ever feeling diagrammatic or self-consciously declarative is no small miracle of dramatic construction, though her facility and fluidity with tone shouldn’t surprise any who saw her previous feature “Everyone Else” — a sexy, funny, emotionally battering beauty of a breakup drama — seven long years ago. Though she has kept herself busy producing for Miguel Gomes, among others, in the interim, one hopes a deserved Cannes competition berth earns her latest (a complicated commercial play, it must be admitted) enough international exposure to hasten further projects of her own.

In case you’re wondering, “Toni Erdmann” is the name of neither protagonist in the film — until, following a mid-narrative segue into brazenly extended bluff-calling and curiously cathartic roleplay, it kind of is. A deliberate, gradually farcical opening scene introduces Winfried Conradi (Simonischek), a divorced piano teacher aimlessly whiling away his semi-retirement in suburban Germany, as a habitual master of prankish disguise, practising multiple personae on a bewildered postman. When his beloved, elderly mutt finally gives up the ghost, Winfried has even less to build his life around than usual; reconnecting with his only child Ines (Hüller), now a thirtysomething, pantsuit-clad corporate go-getter stationed in Romania, becomes his next project.

Trouble is, Ines is less outwardly keen to bridge the gap than her father is, particularly when he turns up unannounced in Bucharest for a surprise weekend visit. (A clever, pose-matching cut by editor Heike Parplies takes Winfried from mourning in his garden to idling against the office greenery of Ines’ office lobby, neatly dramatizing a rash impulse in one wordless swoop — even at such extravagant length, the moment-to-moment economy of Ade’s filmmaking frequently impresses.) What ensues is 48 hours of wince-inducingly believable emotional cruelty and cluelessness, as Ines half-heartedly drags Winfried to a series of professional engagements and they progress from terse niceties to searingly acute confrontation. “Are you really human?” he finally snaps at her, in one of those rupturing parental gaffes that even an immediate apology can’t erase.

An entire film could have been constructed around that nightmare weekend, but “Toni Erdmann” is only getting started. To synopsize events much further would be to impede viewers’ enjoyment of Ade’s consistently unpredictable relationship anatomy, as well as the ever-more-precarious trapeze walk of its heightening comic tone — as the fallout from Ines and Winfried’s falling-out subsequently colors pained interactions with her friends, boyfriend and colleagues, and her depressive nature, generally held in check, begins to unravel. Father and daughter are far from done, too, as he keeps resurfacing in alternative guises: Most aggravatingly to the fearsomely capable Ines, she finds that she’s taken more seriously in business with a man at her side, even one as sloppily uninformed as her father.

In a glorious, risk-it-all final hour, Ade and her actors attain a cleansing yet conflicted sense of emotional release through a series of wild, nervily sustained comedic set pieces that lay the characters bare in more ways than one. Hüller has already proven herself, in such vehicles as Hans-Christian Schmid’s “Requiem,” an actress of uncommon intuition and expressive intelligence, though she hasn’t previously been handed a scene quite as soul-testing as the three minutes here that find her raggedly belting an impromptu karaoke rendition of Whitney Houston’s “The Greatest Love of All” with riotous, to-hell-with-it personal conviction — a feat that rightly earned a rare mid-film ovation at the film’s Cannes press screening. (It’s an inspired choice: The song’s corn-syrup lyrics are so cloyingly on-the-nose in a story of self-empowerment and parent-child affection, they somehow come around to being moving.) She’s matched beat for beat in technical bravado and internal insight by Simonischek, a Austrian veteran of stage and TV, who’s unafraid to go big on the clownish aspects of Winfried’s personality, while zeroing in on the very specific, deep-rooted sadness that drives them.

Ade, likewise, pulls off grand emotive gestures while grazing across subtler dramatic nuances so casually observed — thanks to Patrick Orth’s determinedly unshowy but rigorously character-fixated camerawork — that they seem almost accidental. At one point, focus is fleetingly pulled from Ines’s inner turmoil as she glances down from the lofty heights of her company tower to a swirl of destitute human activity in a crumbling Bucharest shanty so many floors below. Not a word is said about it, but like all great humanist filmmaking, “Toni Erdmann” keeps an eye out for life at the edges, even when the lives in focus consume a whole lot of energy.

Guy Lodge, Vanity Fair, May 2016