In a remote Louisiana swamp along the Bayou Tourterelle, raccoon brothers Bingo and J'miah have just been appointed Official Sugar Man Swamp Scouts, raccoon guardians tasked with watching the swamp for danger and monitoring warnings from headquarters: a rusted 1949 DeSoto Sportsman car hidden on a knoll. Their standing orders include heeding the Voice of Intelligence from the DeSoto's radio and, in an emergency, waking the Sugar Man. The Sugar Man is an ancient creature of the swamp, taller than Sasquatch and the Yeti, with hands as wide as palmetto ferns. He has slept underground for decades, guarded by his gigantic pet rattlesnake, Gertrude, and when angered, he tends to throw things.
Twelve-year-old Chap Brayburn grieves the sudden death of his grandpa Audie Brayburn, who taught him everything about the swamp. Audie's special phrase for Chap was "Nosotros somos paisanos," meaning "we are from the same soil." Chap's family runs Paradise Pies Café, a small restaurant and home where they serve fried pies made from wild muscovado sugarcane. Their landlord, Sonny Boy Beaucoup, who owns the entire Sugar Man Swamp, has raised the rent to an impossible sum. Chap clings to his grandfather's birder sketchbook, which holds drawings of every bird Audie saw except the ivory-billed woodpecker, a species most consider extinct. Audie claimed to have photographed the bird in 1949, but the photo was lost inside the missing DeSoto with his camera and ammo can.
On their first night alone, Bingo climbs the tallest longleaf pine while the height-fearing J'miah waits below. From the treetop Bingo spots a blinking red star he names "Blinkle," but mysterious rumbles shake the tree and send the brothers racing home.
Threats to the swamp multiply. Jaeger Stitch, the World Champion Gator Wrestler of the Northern Hemisphere, plans to turn the swamp into a wrestling arena and theme park, destroying hundreds of old trees and paving 2,000 acres of marsh. She has partnered with Sonny Boy, who dismisses a 350-year-old blood pact signed by his ancestor, the pirate Alouicious Beaucoup, to protect the swamp after the Sugar Man flung several pirates through the air. With Audie dead and the Sugar Man declared extinct, no one remains to oppose development. When Sonny Boy and Jaeger visit the café to unveil their plans, Chap challenges them. Sonny Boy makes a mocking deal: If Chap can produce proof of the Sugar Man, Sonny Boy will give him the entire swamp, signed in blood.
The mysterious rumbles belong to the Farrow Gang, 17 feral hogs led by the massive boar Buzzie and his mate Clydine, descendants of hogs brought to the New World by the conquistador Hernando de Soto. A terrorized fox tells them about wild sugarcane along the bayou, and the gang turns south toward the swamp.
A thunderstorm triggers the DeSoto's radio, and the Voice of Intelligence warns that hogs are heading toward the swamp. Bingo and J'miah realize they must wake the Sugar Man. They find Gertrude deep in the forest, and she tells them the safest way to rouse the Sugar Man is with fresh sugarcane, but her supply is gone. When the brothers race to the canebrake, thousands of hissing rattlesnakes drive them back, as no one has told them the lullaby that calms the snakes.
Chap works to save the café. Coyoteman Jim, the overnight DJ at local radio station KSUG and Audie's old friend, creates a commercial declaring the pies will "Kick. Your. Booty!" Customers line up from the door to the road, and cash fills a pirogue, a small canoe, that Chap has set on the back porch. During his cleanup of the DeSoto, J'miah discovers Audie's ammo can beneath a seat, containing a harmonica and three photographs: a surprised armadillo, the ivory-billed woodpecker, and a fuzzy face that is the Sugar Man, accidentally photographed by Audie in 1949. J'miah props the photographs on the dashboard.
When a lightning strike activates the radio, the brothers hear the pie commercial. Bingo realizes that pies made from the same sugarcane might substitute for the raw cane. The brothers sneak into the café at night and steal an armful of pies, but back at the DeSoto they devour all but one. That single pie is all they have to wake the Sugar Man.
The next morning, Chap discovers the break-in but finds enough pies remain for the day's customers. Meanwhile, at the Beaucoup family Homestead, Sonny Boy discovers a mounted ivory-billed woodpecker specimen collected by his father, Quenton Beaucoup, in 1949. The narrator reveals that Quenton's death, officially a heart attack, was actually the Sugar Man's wrath for killing the bird.
The brothers carry their last pie into the deep forest, but Gertrude surprises J'miah and swallows it. In his panic, J'miah scrambles up a magnolia tree, conquering his lifelong fear of heights. Before Gertrude can resort to biting the Sugar Man awake, she produces a massive sugary burp. The aroma of muscovado fills the lair, and the Sugar Man murmurs "Yummmm . . . sugar . . ." before sitting up for the first time in over 60 years.
Sonny Boy, Jaeger, and 22 dignitaries arrive at the café for the groundbreaking, carrying gold-plated shovels. Chap serves them pies but refuses Sonny Boy's cash, saying the pies are on the house. Sonny Boy kicks over Chap's pirogue, scattering the bills, and taunts him about the Sugar Man. The dignitaries march toward the canebrake, ignoring Chap's warnings, and encounter thousands of rattlesnakes. They flee in terror. The Farrow Gang arrives from the opposite direction and gorges on the sugarcane. The Sugar Man, carrying Bingo and J'miah on his shoulders, reaches the canebrake. Enraged, he grabs Buzzie by the back leg and flings him into the sky, then launches Clydine and all 15 hoglets after him.
While everyone else flees, Chap races toward the canebrake singing the rattlesnake lullaby. He finds the Sugar Man at the water's edge. The Sugar Man recognizes Chap as Audie's grandson and speaks the familiar phrase: "Nosotros somos paisanos." The loneliness Chap has carried since his grandfather's death grows lighter. The Sugar Man commends the raccoon brothers, then returns to his lair to sleep.
Chap tries to photograph the Sugar Man with a customer's forgotten cell phone, but the battery is dead. At dawn, he wanders the bayou and spots sunlight glinting in a thicket. He hacks through the brush to discover the DeSoto's chrome hood ornament. Inside the car he finds raccoon tracks and three photographs on the dashboard: the armadillo, the woodpecker, and the Sugar Man. The Sugar Man photo is the proof Sonny Boy demanded. Chap realizes, however, that revealing it would attract what Audie called a "swarm of hornets," thrill-seekers who would destroy the swamp searching for the creature. He sets the photo back on the dashboard, leaves pies for the raccoons, and walks away, keeping the secret.
The flying hogs crash through the porch roof of the Beaucoup Homestead. Terrified by this proof of the Sugar Man's power, Sonny Boy signs a deal in blood turning over the entire swamp to Chap and nails it to the front door. A black feather with a white tip is found tucked behind his ear. Sonny Boy leaves for the desert, and Jaeger heads for South America. The cane grows back, the old trees stand, and the swamp is saved. Chap, now owner of the swamp, stretches his arms wide and declares, "This is paradise."