She is a beautiful wealthy heiress who travels on an expedition to Africa and later becomes the love interest (later wife) of the titular character.
Ursula travels to Africa to have one last adventure before she gets married to Lyle Van de Groot (growing tired of the pressure, her mother has to be part of high society). Much to her surprise, he shows up on her trip (having tracked her with Max and Thor) and causes trouble for her and her guides (sending one falling from a bridge at one point). At a campfire, Kwame recounts a story of The White Ape, a mythical being of the area. The next day, Lyle drags Ursula away from the camp to look for The White Ape (hoping it'll bring the trip to a quick end), when they are approached by a lion. Lyle makes a break for it, tripping over and knocking himself out. Ursula is about to be attacked, when George appears and fights off the lion. It tries to pounce once more, but she is carried away by George via vine. They crash into a tree, knocking her out and forcing George to bring her to his tree house.
The following morning at his treehouse, she wakes up, only to be met with Ape, George's roommate. She cowers in fear as he beings her a tray of breakfast. George then arrives and asks if she's feeling better. She's convinced she's dreaming, made even more strong when Ape begins to speak to her. She faints (having contracted a slight fever) and George discovers she's the female of his species while tending to her.
Later in the day, she wakes up, remembering what had happened yesterday and thanks George. She asks him for helping finding Lyle and the rest and she's introduced to Shep, George's pet elephant who acts like a dog. They begin their search, but eventually she loses interest in getting rescued and instead joins George on his exploits, including helping out Little Monkey and getting a vine swinging lesson.
Soon, George begins to have feelings for her and asks Ape for advice. In a "big and expensive waterfall set," George tries to use of gorilla mating rituals on her, but with no success. At night, she shows George a ring she considers good luck and gives to him as a memento. They then share a romantic dance around the campfire.
The next day, Lyle finally finds Ursula and tries to get her to come back with him. George rushes toward Max and Thor to not shoot Ape (who reveals he can talk) and is shot by Lyle. Ursula brings him back to San Francisco to take care of him. It is there that her best friend, Betsy, begins to suspect an attraction between the two.
During George's stay, Ursula does find herself starting to fall for George, after his lesson in jungle calling for confidence and his sensitivity. When Beatrice convinces George to leave her alone and head back to the jungle, Ursula finally admits she loves him and goes after him, aiding him back in the jungle during a fight.
Lyle shows up to forcibly marry Ursula (now an ordained priest), but ends up sending their raft down the rapids. George comes to her rescue and they declare their love for each other. They then marry and Ursula stays in the jungle with George, with whom she has a son, George Jr.
Ursula has now been living for five years in the jungle with George and their son. But, she is soon finding their marriage in trouble, as George is spending most of his time with his animal subjects rather than her. They are able to share a romantic evening alone.
Beatrice then visits on Junior's fifth birthday and tries to tempt Ursula back to civilization with many presents (make-up, dresses, etc.) as part of a plan to get her out of the jungle and back into Lyle's arms, and to destroy George and his jungle. George eventually takes them to Las Vegas, to help Ape with his gambling debts. George tries to remedy her "five-year itch" with a backscratcher, and then takes them to an animal show (which doesn't please her very well). When Lyle strikes out in trying to get her back, Beatrice calls in Betsy and more of Ursula's friends to convince her that the jungle will change her, which is proven when she shows extreme strength in their exercise activities. Despite everyone telling her around a dinner table that George won't ever think of her first, she declares she's the luckiest woman for having him and makes a jungle call of love.
Beatrice has a hypnotist brainwash Ursula and her friends into forgetting George and convincing her she's married to Lyle. Beatrice tells this to George, who rightfully gives up and leaves her with his good-luck shark tooth as she sleeps. Ursula is brought back to San Francisco, not remembering ever marrying Lyle and seeming confused.
At night, Ursula pines to Betsy that something is missing in her life. When George gets word that Ape lost the deed to Ape Mountain, he visits Ursula to bring her back with him. She tells him she's married ("Unfortunately.") and has no idea who he is, but finds herself smitten with him anyway. As George carries her out, he accidentally knocks her unconscious on the wall. Back in the jungle, George leaves Ursula to sleep in the treehouse hammock while the rest fight off the impending bulldozers.
She wakes up just as Lyle and Beatrice arrive to reclaim her. Ursula has no choice but to go along, leaving the shark-tooth with George, believing it's rightfully his. Under Ape's advice, George fights for the woman he loves and subdues Lyle. He shares a passionate kiss with Ursula, which undoes the hypnosis. Not long after, Ursula and George renew their vows, where George promises to spend more time with her.