Cookie Chomper III is an episode of The Chipmunks series.
While Dave is working late, Theodore finds a little, lost kitten who came through an open window. However, the Chipmunks soon realize that Dave might not approve, as he's allergic to cats, so they decide to keep it a secret. The next morning, they argue about what to call the cat. Theodore wants to call him "Cookie," but Alvin wants to call him "Chomper." Simon breaks up the fight and decides to use both names, thus giving him the name: Cookie Chomper III. When Dave's outing is cancelled due to his allergy, his date, Roxanne, comes to the house to make dinner. During dinner, Cookie Chomper III comes downstairs and Theodore notices him under the table. They try to get him but accidentally shake the table causing Dave to look underneath. Roxanne is impressed at the sight of the little cat, and Dave decides to let the boys keep him. Simon eventually finds a cure for Dave's allergies. Simon makes a bed for Cookie and Theodore gives him his teddy bear; they both tell him goodnight and that they love him. Alvin also secretly tells Cookie he loves him but takes the teddy bear believing he is tough enough to sleep without it.
That night, Cookie Chomper III jumps out the window by accident and is hit by a car early the next morning and everyone is very upset. The Chipmunks each respond to their grief in their own way. A distraught Theodore denies Cookie's death, insisting he is just lost and trying desperately to find him. Alvin angrily takes all of the house plants outside and orders a woman and her dog to get away from their house, refusing to experience the pain of loss again. A depressed Simon sits in their room curled up while Dave's attempts to cheer him up with his favorite hobbies prove futile. Some time later, the boys are tearfully blaming themselves for Cookie's death. Theodore blames himself for not checking the window being closed while Simon blames himself for not letting him sleep with Theodore. Even Alvin is unable to hide his sorrow and blames himself for taking the teddy bear before breaking down in sobs. Dave tells them that they have all the great memories of Cookie Chomper III, leading into the song "Beautiful Memories." As they reflect on the good times they had with Cookie, the chipmunks are finally able to come to terms with their grief and look on proudly as Dave places Cookie's collar on a plaque made to honor his memory. Later that day, Dave takes the Chipmunks to the animal shelter to get a new pet. Simon is initially upset by the idea, but when the puppy they choose plays with his glasses, Simon comes to accept the new puppy and love her. As they return home, Dave sneezes so Simon tries again to cure his allergy, but Dave refuses.
- This episode marks the first appearance of Lilly.
- This episode was inspired by Ross Bagdasarian, Jr. and Janice Karman's dog, Tiger Lilly. Like Cookie Chomper III, Tiger Lilly was also run over by a car and killed; The Chipmunk Adventure was dedicated to her memory.
- This episode somewhat contradicts A Dog's Best Friend Is His Chipmunk since Dave had an allergic reaction to dogs, while in this episode, he has an allergic reaction to cats. However, oddly enough, Dave develops an allergic reaction to dogs near the end of this episode.
- During the dinner with Roxanne, Simon is wearing a white jacket and tie, but at a closeup of the Chipmunks saying "Can we keep him?" he is wearing his ordinary blue sweater.
- This episode is apart of the Alvin's Thanksgiving Celebration and Driving Dave Crazier DVDs.