- “'I always knew you were good inside'”
- ―Puss In Boots[src]
Being a mastermind, Humpty is very clever and is able to invent extraordinary devices and manipulate unwitting people like Puss into doing his dirty work. He is also quite greedy and a bit of a backstabber as he framed Puss for his crime and nearly got the town destroyed just because he didn't want to return the goose. Despite his bad qualities, Humpty has a heart of gold and considers Puss a brother; he even sacrificed himself to help save the town.
He is very clever and adventurous.
In the film, Humpty first appears in the underground bar, revealing that he had hired Kitty Softpaws to bring Puss to him. He had located the magic beans that he and Puss spent their childhood searching for. However, Puss refuses, saying that Humpty is a traitor (which the egg denies) and leaves.
Later on, Puss tells Kitty that Humpty was his only friend at the orphanage that they both grew up in and not his brother. However, as they grew up, the harmless pranks they performed as children soon turned into crimes. This changes when Puss stops a bull from killing the head soldier's elderly mother. Puss, the new town hero, had less time to spend with Humpty, leaving him desperate, he attempts to steal without Puss, landing him in jail, until Puss bails him out and tells him he is not stealing anymore. In his desperation, he wakes up Puss one night, telling him he owes Little Boy Blue (the orphanage bully and the reason they became best friends) and his gang money, so asks Puss to help him leave town. When Puss gets him over what he believes to be the town wall, he realizes in horror that the "town wall" was actually the wall around the town bank, which Humpty had just robbed. Humpty escapes with all the money in the bank as the alarm goes off. The police arrive immediately, and, seeing Puss with Humpty, believes he helped in the crime.
Wrongly accused, Puss flees with Humpty in their cart, which is destroyed on the bridge, and all the money in the town falls in the river. In his desperation and depression, Puss jumps in the water. This event is what leads to the frosty relationship between Puss and Humpty. Later, seduced by Kitty, Puss agrees to go with them on their journey. Eventually, they steal the magic beans from Jack and Jill, an act which nearly costs them their lives. Soon after, they reach the only soil in which the magic beans can grow. In the clouds, they sneak into the long-dead giant's castle, steal the golden goose, and escape. After they celebrate and go to sleep, Jack and Jill come and knock Puss out. When he wakes up, he follows their trail to his hometown, where he is shocked to find Humpty handing out golden eggs to the residents. Humpty explains that it was all as part of his master plan to get revenge, and that everyone, the bar patrons, Jack and Jill, even Kitty, worked for him. He then has Puss arrested. While Puss is in jail, Puss learns that the Great Terror, the monster they encountered in the castle, will come and destroy the town in order to retrieve the Golden Goose (which was Humpty's plan all along) as the Great Terror is a giant goose who is the mother, and the Golden Goose is its baby. Puss, however, convinces Humpty against it. At the same time, it is also revealed that Jack and Jill only pretended to work for Humpty since they had bigger plans and were planning to betray him all along.
However, it is too late. As the Great Terror descends on the town, Humpty helps lead it to the bridge, where he sacrifices himself so Puss can give the mother the golden goose. As the mother is about to leave, Puss sees where Humpty landed in the canyon, where he sacrificed himself, a golden egg surrounded by eggshell. The mother takes the egg back with her, and Puss says to himself, "I always knew you were good inside." Though during the end credits, Humpty is seen in his normal form, dancing on the mother's back with the golden goose. Whether Humpty is dead or not is left uncertain.
- Humpty in seen during the dancing scene, when the cat yells in a loud voice...humpty is seen playing a guitar
- His grave is seen in Shrek 4-D.