Throughout the third film, she pursues the Four in hopes of having their heads as trophies, especially Alex's. She first appears in the film when she is called by the casino manager and chases the animals through Monte Carlo. All of her assistants are injured in the chase, but she continues to go after the animals and eventually corners them at the Hotel Ambassador. The Four escape on a makeshift plane, which eventually crashes.
Later on she goes to the plane's crash site and discovers the animals ran away with the circus. She jumps on a train to Rome and when she arrives, she spots King Julien and Sonya on their date. DuBois steals a police bike but crashes it into a fountain and is arrested by the police, who look like her men.
Later she escapes from prison and regroups her injured men, managing to revive them with a song. She tracks the circus to the Alps and then to London and almost catches Alex but is tied up and shot out of a cannon by the penguins. She later ambushes the Four when they make it back to the Central Park Zoo. But before she could claim her prize, she is then discovered by the New York zookeepers, who assume she was returning the Four.
Near the end of the film, the mayor of New York presents DuBois with a check of one million dollars, but she tears it and says it was only about Alex. The audience cheers, but she seizes the opportunity to shoot Alex with a poison dart hidden inside a foam finger. However, Circus Zaragoza comes to the Zoosters' aid. DuBois' men were eliminated by the elephants and Sonya the Bear on a Ducati motorcycle, the latter sending DuBois crashing into the reptile house. Emerging from the rubble as deadly aquatic cobras slither about, DuBois captures a fleeing Stefano and attempts to reach for her dart gun, only for Mort to snatch it. Alex and Gia the Jaguar manage to rescue Stefano, the former ending up with DuBois in freefall, right above the penguin habitat filled with the aquatic cobras. DuBois swore that if she was going down, she'll take his head. Alex managed to turn the tables on her as he whistles for two dogs on rocket shoes to uplift him as a makeshift jetpack. He then dumps her in his former habitat, where the animal control officer roaring with rage. Mort then tranquilizing her. In her sedated state, she was suggestible as Alex ordered her to sit, roll over and stay. The penguins then stow DuBois in a cargo box along with her assistants to Madagascar, just like how Alex and his friends were shipped in the first film.
DuBois is the head of pest control in France. She is very ruthless, determined, devious, and holds a strong hatred for animals. In her first appearance she reveals that she strangled her first parrot, flushed down a goldfish, and punched a snake when she was only 7 years old. A unique habit she has is that she puts on red lipstick (with only two strokes) when she discovers something. DuBois has shown she has superhuman strength as she crashed into a big glass windows and brick walls with ease just by running into them. She also has a strong sense of smell seeming to track down animals by smelling the air and licking the ground where animals have already walked on.
Role in the series
DuBois has no apparent role in the SpongeBob series, but it is possible she will return. But it will be tough for her after being shipped off to the wild with her associates. But she has already proven herself to survive almost anything during her scheme.