Perri is the titular main protagonist of Disney's 1957 live action True Life Fantasy film of the same name. She is a female pine squirrel who lives in Wildwood Heart and falls in love with a male squirrel named Porro.
Perri is born in the hollow of an oak tree that was previously struck by lightning. She enjoyed being with her brothers and was born blind like other creatures until she could finally open her eyes and see the sunlight outside their home. Perri's father lives outside in a nest near their tree to keep an eye out for danger, while Perri's mother heads out of the nesting tree to feed her young.
While Perri's mother heads out to find food, she is being stalked by a marten and the birds warn her about her presence. A chase is ensued until she chases her back into her home, where she tries to claw her way into the hole. Perri's father witnesses it and distracts the marten to save his family, but ends up getting killed. However, this is the perfect distraction, as Perri's mother can lead her young to their father's nest, while the marten feeds her young. But the marten finishes her meal and Perri is the last baby to be moved. The marten tries to reach Perri and her mother comes to her rescue. Perri's mother manages to rescue her, while the marten is distracted by a raccoon attacking her nest.
As she grows, Perri starts to learn how to climb branches as the time to teach their offspring survival skills comes. As she grows into maturity, she and her brothers play around as they have learned their ability to leap until a magpie interrupts their performance in annoyance. She tries to make friends with a pair of hummingbird chicks until their mother intervenes and fends her off.
She sets off to look for other squirrels and tries to mimic a flying squirrel, but lands in the world from below the trees, where she encounters other creatures she fears. She encounters a ground squirrel and makes friends, but eats too fast and the chipmunk drives her away. She gets attacked by a woodpecker and stumbles upon the great forest king, Bambi. She happily greets one of Bambi's children until they are alerted by a flock of birds cawing about a killer on the loose. She returns to her home, only to discover that her family and home have been destroyed. She realizes that she's being stalked by the marten who killed her family and she chases her, but she manages to escape by crossing a river, only to get attacked by a bobcat. The bobcat corners Perri on a tree branch until a brave squirrel named Porro intervenes and fends off the predator. Perri sneaks past Porro's territory and settles in another tree. She sees the marten try to cross the dam to get to her, but the dam breaks and the current carries her back to shore. Perri and the marten call out to each other and the marten leaves in utter defeat.
Perri stores her home and notices Porro still reconstructing his nest as autumn arrives. She sets out to find more food and enters unfamiliar territory. She gets knocked down from a tree by a goshawk and gets attacked by a weasel. Perri is chased up to the top of a tree, where she again gets knocked down by the goshawk. The weasel fights Perri until the goshawks swoops down and kills the weasel, while Perri manages to escape.
When winter comes, Perri witnesses the marten once again try to cross the river, but fails. When Perri hibernates, she dreams about owls and rabbits under a full moon.
When spring returns, mating season comes and Perri knows it's time to mate with Porro. Perri responds to Porro's mating call, but a lightning storm interrupts their romance and causes a wildfire. Porro is forced to hide in his hollow log and Perri is chased up to a tree. She eventually climbs down and crosses a river, where she finds a raft with a bobcat on it. She huddles with the bobcat until the rain puts out the fire. While Porro searches for Perri, she arrives back at Porro's log and waits, unaware that the marten has followed her. Porro returns from his search and warns Perri about the marten's presence. He drives her away and is cornered onto a branch, unaware that the bobcat is stalking them from below. The branch breaks and they both plunge down towards the bobcat. The bobcat mauls the marten to death and Perri mourns over Porro. However, Porro manages to survive unscathed and they both spend a peaceful moment with each other.