It starts with a tantrum. A toddler, Kun, clambers down a set of stone stairs into a garden. Before he takes another step, something in the corner of his sight makes him stop. The camera swerves around him like it’s gliding on air to reveal what lies in his gaze: the garden has melted away; in its place is a lush rainforest under a grand glass dome. Standing amongst the trees is a teenage girl in a school uniform, towering over Kun with an irate scowl on her face—the future version of his newborn sister.
Mirai is not a time-travel film in the traditional sense, though director Mamoru Hosoda has explored this sci-fi staple before. In his breakout film The Girl Who Leapt Through Time, Hosoda filters the device through a coming-of-age narrative, exploring the implications of time-travel when used selfishly. Mirai plays with time once again, but it moves beyond the traditional sci-fi tropes we’ve come to expect. The time-travelling that occurs in Mirai is cerebral—we’re never led to believe that what we see is real. Instead it takes place entirely within the confines of the imagination. And when that imagination belongs to a 4-year-old boy, the boundaries are limitless.
Kun’s journey through time is triggered by the arrival of his baby sister, Mirai. He struggles to accept this change in the family dynamic and the accompanying feelings that arise within him. Jealousy is undiscovered territory—as a former only child, he’s never had to compete with anyone for his parents’ affections. It’s not a good look on him either. To put it simply, Kun acts like a brat—all infantile anger and frustration packed into his tiny frame. These charged emotions manifest themselves in destructive ways: hitting Mirai with one of his many toy trains; making a mess of his home; heated declarations of hatred without the knowledge of the weight of his words. Kun yells “I don’t like Mirai,” several times, and each one stings and lingers. Kun doesn’t really hate Mirai, but it’s the ugliness it has brought out in him which he detests. The consequences of his actions become a self-taught lesson in humility and responsibility. The film plays out in a series of episodic vignettes: a tantrum is triggered, and as he walks into the garden, he is transported into a vision occupied by members of his family from the past, present and future. The most important, of course, is the future version of his sister Mirai.
The film doesn’t provide a logical explanation for all its otherworldly occurings. A few rules are established: the Mirai of the present and future cannot co-exist; she can also interact with objects in the real world, suggesting that she is a physical being. But adhering to a strict set of guidelines is not integral to the story. What strings these series of events together is Kun’s emotional journey. It’s the process of learning how to be a big brother which gives the film its potency.
Mirai is less a film that plays with time as it is a film about time: how we change, what remains, and what connects people separated by it. The “butterfly effect” is a well-worn trope by now, but in Mirai it’s used to create a much more emotional effect. The film traces Kun’s family tree, examining seemingly inconsequential moments that were, in fact, vital in sprouting new branches. In one frustration-induced vision, Kun teleports back in time to a rusty garage in rural Japan where he finds a chiseled young man, his great-grandfather. Injured in a World War II battle, he’s taken up horse riding and motorcycling, and brings the nervous Kun along for a ride. Kun is shaking with fear, terrified of the speed at which the horse gallops. “Don’t look down no matter what,” his great-grandfather advises. In the next scene, Kun is learning to ride a bike in the park. As his father cheers him on, Kun pedals with determination and doesn’t look down. In Mirai, discovering your own familial past is a feat of time-travel in itself. Despite having never met him, Kun feels closer to his great-grandfather through shared experience. It’s a connection that stretches across generations. Later, Kun learns that if his great-grandfather had never injured his leg in the war, he would not have married his great-grandmother—continuing a chain of events that ends with Kun, cycling on two wheels for the first time.
On the surface, Mirai is an unconventional family drama, mapping the uneven terrain of sibling relationships in their initial stages. But beyond that, it’s a melancholic love letter to growing up. It memorializes those important milestones, while also ruminating on how much time seems to drift on by. I’m not a parent, but I am an aunt. My nephew is a bit younger than Kun—a loveable brat not unlike Kun, who always needs to be distracted with toys and TV shows and attention. He’s a kid, basically. Living a continent away from him, I don’t see him that much, and when I do he’s noticeably different. He’s grown a few inches, and he’s walking instead of crawling. Growing up, I never understood why my distant relatives would fawn over me, yelling about how much I’ve changed. Now, seeing my own nephew grow out of the cot before I can even register it, I understand. They do really grow up so fast.
This is something that Mirai captures with astute tenderness. Time is a fickle thing, a slippery substance that escapes your grasp before you’ve even had a chance to comprehend it. Hosoda’s camera moves like its very own time machine, progressing from scene to scene like you’re accidentally sitting on the fast-forward button. A grumpy Kun yells for attention from the bottom floor of the house, and the camera follows his shrieks, flying up the stairs to his mother in the bedroom. Kun is there now, too, screaming once again. Hosoda weaves several montages like this, embodying the monotony of frustration that Kun feels, reciprocated in turn by his parents who are barely staying afloat. Daily routines bleed together until they are indistinguishable from one another. It’s in these moments where time slips away before our very eyes. One day is gone in an instant, and Mirai is a few months older in what feels like a few minutes.
This loose temporality is present within every element of Mirai. The film begins with an overhead shot from far above. As the camera moves closer, the lines become more defined. Nestled within rows of typical suburban homes is a long and narrow block of stone and slate. Kun’s father is an architect, explaining the peculiar design of the family home. Each room is sectioned off into levels that continually elevate: the bedrooms on the upper floors, the kitchen below, the garden in the middle, and a playroom at the bottom. In this unconventional design, Kun’s personal space is separate from the rest of the house, emphasizing his feelings of isolation. The garden also becomes a physical and metaphorical center, in which Kun’s time-travelling visions take place.
Hosoda recruited a real-life architect, Makota Tanijiri, to design the modernist home. While it’s visually intriguing, it also serves a larger purpose, reflecting the theme of growing up. At a Tokyo exhibition for Mirai, Tanijiri explained the design: “A child will be able to see the bottom room clearly from the garden, but an adult will only be able to see what’s right in front of them. The child’s view will change as he grows up.” The home itself becomes integral to Kun’s process of learning to be a brother, mirroring a physical and internal change of perspective. With Kun’s playroom always in his line of sight, it makes sense that he would repeatedly attempt to escape there in his heated tantrums. It’s a safe place that never feels too far away, hidden from everyone’s prying eyes except for his.
The film’s fragmented representation of time is echoed in the house, which mirrors the convergence of past, present and future. People find themselves in places in time where they don’t belong, while rooms are organized in ways that defy convention. Something always feels a bit off. The viewer is displaced by the promise that there is a surprise to uncover—a little bit of fantasy in the everyday. There’s an element of fun to the house’s design, too, that is only heightened through the child’s perspective. For every child, the house is more than a home, it’s a place for adventure. It’s a lush forest, a mission, a portal to other worlds.
Mirai makes the ordinary extraordinary. Hosoda is a kind of reverse Hayao Miyazaki—the latter explores intimate themes within vast, fantastical worlds, while the former interrogates the quotidian to uncover the magic that surrounds us. Why set your sci-fi in a mythical world or an alternate universe, when all the possibilities are right there on your front door step?
Mirai means “future”—and that’s exactly what a baby is. By the end of the film, Kun has seen generations, contextualizing not only his family but his place within it. Kun ends his time-travelling adventures with the understanding that his family has shaped him into who he is, and that he holds that same responsibility with his sister. Siblinghood becomes a task in writing history, and Kun accepts his new commitment with excitement. After Kun says goodbye to future Mirai, he finds himself back in his present home. Mirai sits in his playroom, and he offers her a banana like an olive branch. They smile at each other for the first time, and both scream with euphoric glee, with the knowledge that they will face the magical, unpredictable future together.