After they accidentally destroy a rental DVD that was overdue for return, Gumball and Darwin try a series of schemes to pay off the $25 replacement fee before Nicole finds out. However, their plan fails to dodge Nicole's parental powers as she discovers the fee and chases them down.
Gumball and Darwin attempt to show their responsibility by babysitting Anais while their parents are at a school meeting. Their attempts to be responsible prove too restricting for the more intellectual Anais, and she soon rebels against her brothers and destroys the house.
Gumball and Darwin grow bored of one another and seek out a third friend to make their lives more exciting. They find a new buddy in their classmate Tobias, but Gumball soon becomes jealous when Darwin starts spending more time with him.
Believing that his life has been saved by Mr. Robinson, Gumball vows to repay his debt by saving Mr. Robinson's life. His acts either annoy or injure Robinson, and as he goes on to perform, Anais and Darwin plan to fake an assassination attempt to lift Gumball's spirits. Song: I Want to Be Free
Gumball and Darwin think that the world will end in 24 hours at the beginning of an impending solar eclipse. The misunderstanding escalates, and the boys discover that their perceptions were wrong as the eclipse passes and nothing happens.
When his clothes are accidentally shrunk in the washing machine by Richard, Gumball is forced to crossdress by wearing Nicole's wedding dress to school. Soon, everyone at his school thinks that Gumball in the dress is a beautiful girl. Though Gumball revels in his newfound popularity, he is disgusted after learning that Darwin has developed a crush on his feminine persona. Gumball sets up a fake going-away party to let Darwin down easy; it works, but Gumball ends up embarrassed after his classma
Gumball and Darwin help Anais get her beloved Daisy the Donkey doll back after it is lost on the way to school and gets taken by Tina Rex. The three sneak into her junkyard home and reclaim the doll, but they accidentally awaken Tina, resulting in a chase; after Tina expresses her fear of the dark, Anais allows Tina to keep the doll out of compassion.
While buying a last-minute birthday gift for their mom, Gumball and Darwin become unwitting accomplices in a stick-up at a gas station. After Nicole, Richard and Anais are taken hostage, the boys discover the truth and prevent the thief from taking the money.
When Masami claims that Darwin is her boyfriend, Gumball vows to help his friend before he gets kissed by her but is constantly distracted by his crush Penny. At a treehouse the girls hang out in, Darwin (unwillingly) and Gumball (just to be near Penny) are dragged along, but Tobias and Banana Joe cut down the treehouse, and the boys' attempt to kiss their respective girls ends in them unknowingly kissing each other.
Nigel Brown assumes that Anais finds her family dysfunctional after seeing a picture drawn by her, so he begins to meddle in their family life; he forces Nicole to relax, Richard to get a job, and enrolls Gumball and Darwin in a behavioral program. Although the results end up much worse, Anais manages to get everyone to listen to her and explain the painting's true meaning.
Gumball and Darwin challenge Richard to a laziness competition, with the loser having to do the winner's chores. However, they soon struggle and decide to call a time-out and find someone to help them; they discover that Larry Needlemeyer, a store cashier, was once lazy, but left it all behind after getting his life together. The boys insistently ask him to help them in their lazy-off, causing Larry to lose his job, car and girlfriend. Their plan fails when Larry refuses to show up, and decide t
Gumball's classmate Carrie, a ghost, is unhappy over her inability to eat. Darwin unsupportively offers she possess Gumball's body, and after doing so, she sends him on a voracious junk-food spree; as her possessions and wild food runs continue, Gumball must learn to say "No" to drive her off.
When the class finds a disfigured Principal Brown in Gumball's school locker, the entire class blames him; Gumball decides to find clues as to who truly did it, discovering that Miss Simian (as well as some random occurrences from Penny, Rocky and Darwin) had caused the incident.
Gumball, Darwin and Richard start a prank war, but the boys' pranks against their father hopelessly begin spiraling out of control, causing chaos in the Watterson household. Songs: I'm a Ballerina, A Music Video
Gumball and Darwin are ridiculed for their martial arts costumes by their schoolmates, and Nicole tries to convince them to take them off, but after witnessing Penny defend them, she realizes that everyone deserves a chance to be themselves. Songs: The Inner Warrior, No More Gi
Gumball is accidentally kissed by his visiting Granny Jojo and, unable to forget the experience, Darwin puts him through a triathlon of traumatic moments that allow him to finally forget the kiss - only to be brutally reminded when Jojo prepares to leave.
Gumball and his friends are invited to a high-school party hosted by Tobias's sister Rachel, but they must find dates in order to attend; he asks Tina to the party, much to Penny's dismay, while Darwin joins him, ending up bonding with Rachel and helping clean up her house after the party.
Gumball and Darwin discover their recently bought video game is defective and return to the store to get a refund; their attempts to get Larry to accept giving them the refund end in failure, and they decide to enlist their father's help, but when steals from the cash register, the manager appears and attacks him. Gumball negotiates with the manager to relent, and he offers them a new console to play the game; upon setting it up, they discover it to actually be a shredder. Song: Refund the World
Gumball decides to help Bobert act like a real boy. However, it soon becomes a battle for his very identity when the robot slowly begins to replace and starts plotting to take over his life.
During a school field trip, Gumball and Darwin ignore their teacher's warning to go around a dangerous forest and, instead, traverse through it. Hopelessly lost, they must use what very little survival skills they have to escape.
Anais tries to "dumb down" in order to have fun with her brothers and father. Gumball, feeling left out, sets up a race in order to win his father back. Song: The Dumb Song.
After being locked in the bathroom, Darwin prepares to tell Gumball a terrible secret, but they are freed by Rocky before he could explain; left annoyed at Darwin for passing off the secret, Gumball begins to pressure Darwin into telling him, but he fails. After locking them in the bathroom again, Gumball learns that the secret was about Darwin's reaction to a sandwich; after escaping through the sewers, Darwin and Anais reveal the true secret - they accidentally posted an embarrassing video of
Mr. Small teaches Gumball and Darwin various but confusing ways of becoming more honest. Song: The Honesty Rap.
With Darwin taken to an institute for geniuses, Gumball tries to become smart (with help from his brain) in order to join him. Meanwhile, Nicole and Richard cope with the possibility of never seeing Darwin again by bringing in Rocky, the school janitor, to replace him as Darwin. Song: You Gotta Think Big.
Richard believes there's a ghost in the attic but is actually Mr. Robinson who Gumball moved up there after entering a catatonic state due to being kicked out by his wife. Gumball and Darwin work on trying to restore Mr. Robinson whilst Richard, unaware of this, sets traps for the ghost.
Gumball and Darwin want to become adults, Richard wants to lose weight. After accidentally having their cereal switched with supplements Richard ordered, Gumball, Darwin and Anais find themselves having very unusual growth spurts.
Gumball learns how to date so he can go out on a date with Penny. It later turns out, however, that he is going to a pet funeral for Penny's pet spider, Mr. Cuddles. Song: Danny Boy
When Gumball turns down an offer to join the Rejects Club, they seek to enact revenge against him.
After Richard finds a toy magic wand in his cereal box, Gumball and Darwin help him believe in magic again; however, Richard's belief in the wand sends him on a power trip, and the boys are forced to reveal the truth to their father.
Ms. Simian cozies up to Gumball in order to win an award.