If 2014's haunting Danish mystery "Borgman" and 2016's taut chamber thriller "10 Cloverfield Lane" had an 8-year-old child in a 30-year-old man's body, it might look a lot like the charmingly, bafflingly bizarre "Der Bunker." This singularly original German import—the feature writing-directing debut of Nikias Chryssos—defies easy genre classification, snubbing its nose at anything resembling convention. What can be assured is Chryssos' ample ability to generate a living, breathing portent. With the narrative so brazenly askew, anything seems possible. Just as surprising is what it thematically transforms into—an idiosyncratically delivered metaphor for the pressures of childhood, the process of taking charge of one's independence, and the ultimate difficulty in letting go.

From out of a snowy forest near Berlin comes a mathematician called simply Student (Pit Bukowski). He has arrived at the door of an underground bunker home where he hopes the solitude will allow him to work on a writing project. Student is taken aback by the oddness of his hosts, Mother (Oona von Maydell) and Father (David Scheller), and their son, Klaus (Daniel Fripan), a grown man who says he's eight years old and acts like it. Frustrated over the lack of progress with his studies, Mother and Father convince Student to play schoolteacher to Klaus. As Student becomes embroiled in the eccentric actions of this family and grows increasingly concerned for Klaus' well-being, he begins to wonder if they have any intention of letting him leave.

Satire, horror and surrealism blur in "Der Bunker," a film of eccentric social mores set in a world resembling a forebodingly charred fairy tale. In addition to the sad-eyed Klaus, being groomed to one day become President of the United States, there are a stream of disconcerting grotesqueries on display. Mother's relationship with Klaus is inappropriate to say the least. Father dresses like a party clown and holds joke nights. And then there's Heinrich, a demonic voice living inside the open gash on Mother's leg. Meanwhile, the crimson glow sweeping across the claustrophobic bunker begins to resemble an invasion from the trenches of Hell. Perhaps, in the end, "Der Bunker" doesn't go far enough with its payoff to match the script's unique ambitions, but the picture excites by constantly evading norms of decency and expectation.