On Middle Island off the coast of Warrnambool, the tiny Australian little penguins have found a home, but the foxes have learned to swim to the island and have decimated the colony. Emily Marsh [Sarah Snook] walks the shoreline, counting the remaining penguins after another fox attack, flanked by her co-worker Zoe [Tegan Higginbotham], her colleague Paul Watt [John Leary], and her friend Jack Jones [Richard Davies]. The atmosphere is quiet but tense, as the team pieces together what the island needs to recover from the losses and what it will take to keep the penguins safe in the long term.
Meanwhile, in the heart of Warrnambool, an eccentric chicken farmer named Swampy Marsh [Shane Jacobson], Emily's estranged father, moves through his barn with a practiced rhythm, feeding his dogs Missy and Oddball. His presence adds a layer of complexity to the town’s delicate balance between tradition and conservation, even as he remains focused on the animals he tends and the care he shows to his family from afar.
At the same time, nine-year-old Olivia Marsh [Coco Jack Gillies], Swampy’s granddaughter, is busy with school and life in Warrnambool. She packs her lunch and opens a gift tied to her mother’s love interest, Bradley Slater [Alan Tudyk], a charismatic figure who has his own plans for the area. Olivia and Swampy disapprove of Bradley, but his influence is undeniable as they drive to school together. The car ride is lively and a touch chaotic, with Oddball playing a role in the morning’s mischief, and Bradley’s idea to promote a whale-watching venture creating a new kind of competition for the penguin sanctuary. Bradley’s plans soon become a whispered debate about what the town should prioritize, and about whether a proposed new attraction could threaten the delicate balance that Olivia and the penguin project represent.
That day at the courthouse, Oddball is given one last chance to behave, a reminder of how the town’s future might hinge on one animal’s conduct. Later, Swampy is called to tend to an injured penguin on Middle Island, a fox attack that leaves the bird vulnerable. He brings the penguin into his home, where a fox that stalks the injured bird is driven off by Oddball. This moment marks a turning point for Swampy, who begins to see Oddball’s potential to protect more than just one animal. Inspired by this, he envisions a plan to save the dwindling penguin colony, one that Olivia eagerly supports and helps to name Pocket, the recovered penguin.
With Pocket healing, they begin training Oddball to guard the penguins at night, and Olivia happily agrees that the dog could become a true guardian. The penguin numbers slowly begin to rise, and Emily learns of Swampy’s plan to focus the sanctuary’s energy on Oddball’s new role. She and Bradley have gone to Melbourne for a break, where Bradley openly proposes that they move to New York City; a future full of possibilities that would pull them away from Warrnambool. Olivia and Swampy stay behind, sleeping on Middle Island for a test run to see if Oddball can truly protect the birds, while Pocket is released back into the wild after his healing.
When Oddball demonstrates his ability to fend off a fox and keep Pocket and his mate safe, the plan to use the dog as a nightly guardian gains momentum. The penguin sanctuary begins to feel viable again, and Emily begins to understand Swampy’s devotion to the animals—and the possibility that the sanctuary might truly thrive. Yet the real challenge lies in keeping the project safe from those who might profit from a different plan. Swampy suspects Bradley of sabotage because he’s so eager about a whale-watching project that could replace the penguin sanctuary, and the tension between family loyalty and conservation grows.
That night, after dropping Oddball off on the island, he nearly loses the dog when Oddball is tranquilized off-screen by an unseen hand. Swampy discovers Oddball in the back of an animal-control van, a tranquilizer wound marking the moment as a turning point for the family and the island’s future. He learns from the animal catcher that Oddball cannot be saved by brute force, but the discovery that Pocket and his mate have laid an egg inspires a new wind of hope. Swampy and Olivia rally to save Oddball, while Emily and Jack discover that some crucial items—tranquilizer guns, fox cages, and darts—have vanished, hinting at a larger scheme at play.
The trio—Swampy, Olivia, and Emily—meet on the beach that connects to Middle Island, with Oddball heading back toward the island to prove his worth. They trail him as he uncovers the saboteur, releasing a fox in an attempt to destabilize the sanctuary. The reveal comes at last: Zoe [Tegan Higginbotham], Emily’s coworker, is the culprit, driven by a boyfriend who runs a whale-watching venture she believes will salvage her own life. Zoe tries to seize Pocket’s egg and destroy it, hoping the eggs will vanish into the sea. Emily confronts her, and Zoe’s plan crashes when she is tranquilized and arrested by Jack [Richard Davies].
With Zoe stopped, Oddball carefully retrieves Pocket’s egg with the help and guidance of Swampy, Emily, and Olivia. In the end, Emily renounces Bradley’s plan to move away and reconciles with Swampy, whose love for his family and the birds remains steady. The sanctuary is saved, and the Maremma conservation project is approved, ensuring a promising future for the penguins and the town that has come to depend on their survival.
