In a sun-baked desert where animals are called Dusties, Ajar [Omar Sy] the cobra and his best friend Pitt [Franck Gastambide] the scorpion swipe a watermelon from a caravan of camels, only to have it snatched away by Saladin [Roschdy Zem], an older cobra who constantly belittles them. The pair are frequent targets of his derision and are treated like outcasts by the desert community. Frustrated with being labeled a “loser,” Ajar dreams of reaching the Oasis, a glittering haven for the green snakes that seems off-limits to Dusties.
Ajar [Omar Sy] disguises himself as a green snake and slips into the Oasis. There he meets Eva [Louane], a green snake who has herself hidden as a Dusty to escape the Oasis’s exclusivity. The two are chased by Secretary birds to the edge of a cliff, and they leap into a river. The disguises wash away, exposing their true identities to each other. Ajar, unable to swim, nearly drowns, but Eva saves him with mouth-to-mouth resuscitation. Ajar and Eva form a cautious friendship, and Ajar finds himself falling for her, even as Eva’s world grows more complicated when she is captured by Omar [Grand Corps Malade], a snake charmer who presets the other snakes for a shopfront life.
Ajar pursues, but he and Pitt are captured by Chief-Chief, one of the secretary birds guarding the Oasis. The two are brought to the birds’ base, where their captors threaten execution. In a bold move, Ajar uses Gary [Vincent Lacoste], Eva’s lazy but loyal brother, as a hostage and the trio escape on the back of a secretary bird, a flight cut short when Pitt accidentally stings the bird, leaving them to flee on the ground.
Meanwhile, Eva encounters a menagerie of snakes Omar has captured, including the coral snake twins, Lulu Belle and Lily Belle, a charming green snake George [Jean Dujardin], a white snake Pietra [Marie-Claude Pietragalla] who clashes with Eva but greets the others, and a red python Rita [Mathilde Seigner]. Omar’s operation unfolds as he plays a flute that hypnotizes the snakes and keeps them under his control. Eva attempts an escape, but the flute’s spell pulls her back. Pietra offers Eva a possible escape through a hole in the basket, but the two are recaptured shortly after.
Gary, Ajar, and Pitt tumble into a cave and are greeted by Glow-Worms. The Glow-Worm King provides directions to Eva but tries to lure them in as prey; the trio narrowly manages to slip away. They later climb into a jeep with tourists, but Pitt becomes separated from the others. A fast-talking sandfish points them toward Souksoukville, a clue that eventually guides their path. Ajar and Gary push forward to an oasis where they rest for the night and begin to open up—Ajar reveals that he and Pitt are among the few true friends he has, while Gary confesses he has no friends at all. Pitt, meanwhile, stays with the tourists and joins a group of scorpions, continuing his own winding journey.
Ajar and Gary discover a well and ride a bucket down to escape a raging sandstorm, eventually arriving in another town. They follow Omar’s advertisements to his store, where Ajar sees Eva and the other snakes trapped in a cage, with George embracing Eva. Misunderstanding the moment as a romantic reunion, Ajar nearly gives up, but a daring move—releasing a ceiling fan that crashes into the cage—frees the snakes. Omar races to seize the flute, but Ajar grabs it first.
The pursuit ramps up around the city as Omar chases Ajar through the desert’s intensifying sandstorm. The chase leads to the top of a mosque, where Omar tries to snatch the flute, breaks it, and grabs Ajar to keep him from falling. In the struggle, Ajar’s skin peels away, and Omar vanishes into the sandstorm. When the storm subsides, Eva and Gary find Ajar and believe him dead, only for him to awaken moments later. Eva realizes that Ajar has crossed a harsh desert for her, and the two share a kiss. Omar reappears but collapses after Pitt stings him, then introduces them to Emily [Elana Dunkelman], a Scorpion Girl from his circle. With Emily aboard, Ajar, Eva, Emily, Pitt, Gary, and Pietra slip away in a tourist car.
As the vehicle pulls away, the fast-talking sandfish returns, perched beside a camel. He sings of a possible future where Ajar and Eva return to the Oasis and teach Dusties and Green Snakes to live together as equals, though the tale remains open-ended and uncertain about what awaits them next.
