To state the obvious, animated films by their very nature allow their creators to transcend the limitations of the real world: Animals talk, trees and houses come to life and coyotes flail in mid-air above canyons before finally resigning themselves to their dusty fate.

The new animated feature I Lost My Body, though semi-realistic in design and execution, pushes the medium’s innate connection to the fantastic in strange and subtle ways. Based on Guillaume Laurant’s novel Happy Hand (which has not yet been translated into English), it’s a deceptively simple story so continuously inventive and expertly executed that it’s easy to accept or even embrace its undeniably absurd premise.

The protagonist of I Lost My Body is a severed hand who (which?) escapes from a medical lab’s refrigerator and scurries through the streets, skylights and sewers of Paris in five-fingered pursuit of its former body. Along the way it passes through various locations associated with said body, a young man named Naoufel who has led a life filled mostly with loneliness and disappointment.

Director Jérémy Clapin, who co-authored the screenplay with Laurant, skillfully balances the film’s two paths with delicate and often startling symmetry. Naoufel’s story, from childhood ambitions to a frustrated adulthood of unfulfilling jobs and failed romance, is convincingly down to earth and believably bittersweet. The film’s other half, the hand’s often arduous journey, is part mind-boggling adventure and part horror film, with bizarre images — the hand crawling across an infant’s chest — and genuinely disturbing moments, as when the hand ends up in the center of a pack of rats on a subway track.

Clapin inevitably recalls the murderous appendage of the 1946 film The Beast with Five Fingers, but without the melodrama or the menace. Unlike his malevolent counterpart, this hand tries to avoid human contact; it has bigger challenges simply trying to cross a street or find its way off a rooftop. The concept may be patently absurd, but Clapin and Laurant bring it off with scenes that are deceptively simple but excitingly resourceful. Even more remarkable, they do it without relying on any overt anthropomorphism. This isn’t a cute, plucky Hamburger Helper cartoon limb. It’s just … an ordinary hand.

Although it’s inevitable that the two narrative lines meet, they finally come together in a moment that is startling yet emotionally effective. It’s a conclusion that is both logical and ambiguous, uniting the film’s parallel paths of the fantastic and the naturalistic. Brilliantly contrived and conceived, I Lost My Body is an exceptional achievement, a film that compellingly endorses the real world even as it turns it into something alarmingly uncanny.