This article originally appeared in Vulture.

A lone samurai clad in white stares up in horrified awe at a gargantuan future city, constructed with neon bright colors, clashing machinery, and aliens speaking in a tongue foreign to his ear. This samurai travels through lands of the mythic and mundane, the natural and the supernatural. Here he is again, alone, in a dense forest. The only sounds are chirping crickets and the fire that crackles before him—until a vision of his long-deceased father rips through the tranquility, admonishing him for his failure. These moments aren’t from a prestige TV series with A-list talent or a long-lost Akira Kurosawa film. They’re from Samurai Jack, the animated series created by Genndy Tartakovsky that premiered in 2001, ran for four seasons, and was revived for a fifth and final season that ended this past weekend.

Samurai Jack follows a young prince (voiced by Phil LaMarr) in feudal Japan trained to finally destroy the shape-shifting, sorcerer-demon Aku (the late Mako Iwamatsu for the first four seasons, Greg Baldwin in the fifth season) that his father could only entrap. Before he’s able to land the final blow with his magical sword, Aku rips a portal through time and flings the young prince hundreds of years into the future. Earth is now a strange dystopia in which aliens, monsters, common folk, and madmen alike struggle to survive under the harsh tyranny of Aku. The warrior-prince—who adopts the moniker of Samurai Jack, although his given name is never said—finds himself without a home or companion, a stranger in a strange land. Samurai Jack was unfortunately canceled in its fourth season before its titular character could find a way back to his own time and finally defeat Aku. In its final, ten-episode season, the show definitively concludes the long, weird, oft-touching journey of its hero. The fifth season picks up 50 years later. Jack has not aged, but the toil of his journey has led him to slip into hopeless despair and madness.

Samurai Jack may be spare on plot, but it brims with emotional complexity and visual splendor. In its sharply constructed episodes that clock around 22 minutes, you’ll find the glint of Blade Runner’s cyberpunk dystopia, the earthy sensuality of Gene Kelly, a glimmer of Wile E. Coyote zaniness, and visual humor that wouldn’t be out of place in Raiders of the Lost Ark. Samurai Jack echoes Frank Miller at his most stark, Akira Kurosawa at his most poetic. It is suffused with the energy and scope of classic epics like Lawrence of Arabia. It moves between moods and genres with such impressive swiftness the series becomes its own strange beast. This flexibility is perhaps why voice actor Phil LaMarr said in an interview with the AV Club about the series, “[I]t’s one of the few things I’ve been a part of that I feel pretty confident I can sit anybody down in front of it, and they will find something to enjoy about it. Grown-ups, kids, old people, babies—you respond to the colors, to the action, to the epic mythological underpinnings. Whatever it is, there’s something there that will blow you away.” But what makes Samurai Jack a stunning piece of art that deserves to be discussed in league with TV’s great live-action, scripted giants is how its visual and sonic landscapes work to create an intimate, even brutal portrait of one of the most human experiences: loneliness.

I was 12 years old when Samurai Jack premiered on Cartoon Network. My younger brother and I would sit in rapt attention in front of the small television in our den to watch the series. We’d beatbox its theme song and take on the exaggerated voices of whatever monster Jack was locked into battle with that week. It took me until the fifth season this year to recognize what about the series has resonated with me so deeply. Samurai Jack is a vestige of my relationship with my brother, whom I’ve been estranged from for several years. And so it feels weirdly appropriate it’s a series that poignantly encapsulates the soul-warping effects of extreme loneliness that come with isolation and loss I’ve grown almost accustomed to as an adult.

As cultural critic Olivia Laing puts it in her book The Lonely City, people often think of happiness as a “permanent resident.” With the right factors—love of a partner, community, work—loneliness can be staved off. But loneliness can take hold in a crowded room or the arms of a lover. It need not be predicated on being physically alone. Samurai Jack doesn’t treat Jack’s loneliness with ponderous malaise or pretension—it understands that loneliness and longing can take on many shapes and textures. Even when Jack is surrounded by friends and foes, loneliness bubbles beneath the surface. While the idea of loneliness snakes through the show’s plot, it’s most profoundly felt in the visual and sonic choices. After all, the series is remarkably sparse when it comes to plot and dialogue, taking the stoic samurai warrior trope to an extreme. It chooses to let the image of its lead character dwarfed by alien landscapes communicate his painful isolation, where in other shows, and especially cartoons, dialogue would be relied upon. The traditional, antiquated Japanese garb he wears is a constant reminder that he doesn’t belong in this time and place.

In an interview with the Verge, Tartakovsky noted, “One of the things we couldn’t do in the first 52 episodes—it couldn’t be episodic, which hinders your character growth. You can’t have as many ups and downs, because if Cartoon Network aired the episodes out of order, he’s super-dark in one episode, and cheery in another. So that forced us to make him more even-keeled, and we played him as a stoic samurai hero, unaffected by everything he’s going through.” The fifth season indeed shows remarkable growth artistically and thematically, particularly in how Jack’s internal life is given so much focus. But I don’t think Tartakovsky gives himself and his collaborators enough credit. What unifies the series through its experiments in genre, mood, color, and sound is how Jack reckons with his profound loneliness. This is a man whose cultural and interpersonal isolation is never forgotten. It hums beneath the surface of even the most joyful, zany episodes like “VI,” in which Jack works with a formidable warrior woman he finds himself drawn to. This is clear in the very first episode as a young Jack matures into the renowned warrior he’d come to be known as. He vaults between a multitude of cultures and mentors—the serenity of sub-Saharan Africa, the magnificence of ancient Egypt, Tibetan monks, and even Robin Hood. But there’s something about this impermanence that feels haunting, especially since it comes on the heels of Aku’s return, his father’s enslavement, and the obliteration of his family life. In this light, Samurai Jack has an essential truth: Relationships are ephemeral.

I don’t fully believe that Samurai Jack argues this truth is a universal one. But it applies to those of us that pursue our goals with such dogged determination the rest of life often becomes an afterthought. The nature of Jack’s single-minded quest—to travel back to his own time and kill Aku—means he’s always on the move, leaving little time to nurture whatever connections he’s fortunate to have at all. Traveling across the world, saving countless lives from Aku and his minions, has turned him into something of a folk legend. He’s gathered allies along his journey. In some cases, these allies may even be considered friends like the Scotsman (John DiMaggio), a bawdy warrior who has saved Jack from various hijinks (my favorite being when Jack’s memory is wiped by a trio of sirens turning him into a dim-witted, affable ship waiter who comes across like a lost role Keanu Reeves would have played in the early 1990s). Often, Jack seems drawn to people who carry the ghostly echo of his own distinctive emotional state. These are people (and aliens and talking dogs) who travel in search of lost loved ones, aim to reclaim their homelands, or yearn to find a home at all.

It’s hard to choose a single episode that best represents the distinctive undercurrent of loneliness stretching through the series from start to finish. It can be seen in the season three haunted house episode, in which Jack travels to a spirit realm to fight a dragon-esque demonic force. The climactic fight, seen in the video above, is depicted in sketchy black and white. Noises register as if heard underwater at a distance—they’re muted and uncanny. There’s something isolating, even horrifying about the monochromatic spirit realm. The image of Jack tied down in a void of endless white, coupled with the lack of background music throughout the entire episode, makes this one of the show’s most harrowing evocations of how Jack feels, stuck in a future he doesn’t fully understand. Jack beats the demon, freeing the Japanese family that had been trapped by him. For Jack, the family’s reunion is another reminder of what he’s lost along his journey to destroy Aku. His loneliness is intrinsically tethered to his displacement. Perhaps this is why season two’s “XIX” is one of my favorite episodes.

Directed by Tartakovsky and Rob Renzetti, “XIX” begins with a rhythm familiar to anyone who has watched the series. An inventive fight scene, impossible odds, murderous robots, and a village of people forever thankful for Jack’s generosity. What pushes “XIX” into the upper echelon of Samurai Jack episodes comes afterward. Jack travels through distant lands—snowy tundras, mountain ranges, desert vistas, quiet riversides—as the only living creature in the frame. He’s humbled by the grand solemnity of nature. His presence is often minuscule in these landscapes. The sound design is minimal—the whistle of sharp winds, the gentle churn of a river, the clatter of Jack’s geta against the ground—and works to create a representation of Jack’s place in the world metaphorically. He’s a man without home or culture or belonging. Soon, Jack finds himself near a serene river surrounded by lush foliage. His peaceful smile contorts into shock as he recognizes the decaying monuments obscured by the overgrowth. He gasps when he realizes where he is. He’s home. Or at least, what is left of the grand kingdom he called home that flourished hundreds of years ago. All that’s left are ruins. Jack himself is a relic, a ruin, an antiquated figure from a time so long ago, no one else remembers it. This scene is a gut punch for how succinctly it communicates one of the loneliest experiences: when places that once were home have become foreign. In its original run, episodes like this often sat next to more humorous and adventurous chapters, so the series never became wholly depressing. But in season five, partially thanks to the show’s move to Adult Swim, Jack’s loneliness reaches the pitch of madness.

The gnawing loneliness Jack has been living with for 50 years cannot be untangled from the anxiety and madness that seizes him (which isn’t helped by the fact that he loses his sword, the only instrument capable of killing Aku). In the fifth season’s third episode, “XCIV,” Jack stumbles through the forest, bloodied and bruised from a fight with the Daughters of Aku, born and brutally trained for the sole purpose of killing him. The episode makes bold use of color to signify Jack’s physical and emotional state. The ruby-red blood that pours from his abdomen blares like a siren through a calm evening. It immediately separates him from the indigo, aquamarine, cerulean, and midnight blue of his surroundings. The haunting string music, wet plop plop plop of blood on the ground, and his painful groans create a symphony of a man brought to the brink. When a hulking white wolf helps Jack as he hides out in a cave, I wondered: Is this companion a metaphor for Jack’s yearning and growing feral qualities? Or is he a real flesh and blood wolf? He’s both. In moments like this, Samurai Jack’s use of visual metaphor elevates it to the place of folktale.

While loneliness is season five’s primary occupation, the show also does something I never expected: gives Jack a love interest.

Ashi (voiced by the legendary Tara Strong) began as one of the seven Daughters of Aku. She’s the only one of her sisters to survive the showdowns with Jack that take up the first half of the season. But it’s clear from the introduction of these young, myopic warriors that Ashi is different than her sisters. She may spout rhetoric about Aku’s greatness, but there is a tenderness to her, evident in how she yearns to discover the world beyond her brutal training. Ashi becomes a warped mirror image of Jack—the rigorous training, the burden of destiny and great responsibility—which makes their turn from enemies to unconventional friends to romantic partners jarring, but understandable. When they first kissed at the end of “XCIX,” I worried Samurai Jack was crafting a traditional happy ending. If anyone deserves a happy ending, it’s Jack. But traditional has never been a word I’d use to describe the series.

The final episodes introduce some important narrative twists that set up the possibility of a saccharine conclusion. Ashi is revealed to be a literal daughter of Aku when she and Jack face off with the villain after they regain his sword. Evil overtakes Ashi until she’s an automaton cloaked in darkness, with eyebrows of fire, who is incapable of resisting Aku’s bidding. Distraught by losing what has been his only romantic partner, Jack becomes utterly hopeless. Samurai Jack isn’t a dour show, though, so of course Jack is able to beat Aku and helps Ashi fight the evil overtaking her. Realizing she has all of Aku’s powers, Ashi sends herself and Jack back to the past, a mere ten seconds after he was originally flung into the future.

Jack’s hard-earned defeat of Aku is as epic, moving, and artful as it deserves to be. And for a moment, it seems like Jack will be granted an overly sweet ending, as he’s finally returned back to the past he’s longed for. The mentors who trained him come to Japan from their far flung lands. A gorgeous wedding is prepared for Jack and Ashi. But just as Ashi proceeds toward him at the altar, she crumbles to the ground. With Aku killed in the past, Ashi can no longer live given that the events that precipitated her existence never came to pass. She’s a time paradox. She swiftly fades from existence, leaving Jack, once again, alone.

The final moments of “CI” are tinged with sadness, solemnity, and even hope. Jack rides atop a horse through a fog-drenched forest. Its gray tones seemingly echo his own sadness. He sits beneath a tree interrupted only by a ladybug that rests on his finger. He smiles as the sunshine brilliantly illuminates the cherry blossoms that surround him. Jack is at peace with himself, even though he may be lonelier now than he was when the series began. Tartakovsky and his collaborators understand that loneliness has different textures. It can be as tender as a bruise, as brutal as the sharpest blade, as restricting as a coat three sizes too tight. Sometimes it is even a bedfellow so common you momentarily forget its presence. At least it has been for me. But watching the finale of Samurai Jack, which brought me to tears, I couldn’t help but think of my brother and feel an emotional pull connecting me to Jack’s own predicament. In the final moments of the series, loneliness takes on a shape many of us may understand. It’s a bittersweet promise intrinsic to the human condition in which simple joys—the glimmer of sunlight, the quietude of a forest, the presence of a ladybug—are sometimes all we have to nourish us.

See also: This Is What Makes Samurai Jack the Most Visually Audacious Show on TV