The first animated adaptation of the 1960s gag manga series, focusing on the adventures of the identical 10-year-old Matsuno sextuplets, led by the titular brother himself. Aside from the Matsunos, the series also showcases the tales of their rival Chibita, and the constantly job-switching conman Iyami.
Episode 1
Osomatsu and Choromatsu mind Chibita as babysitters, but grow bored and decide to have a mysterious dog take the heed instead. / Dekapan creates a robot powered by spare change that inadvertently leads to disaster in the hands of the sextuplets.
Episode 2
Iyami attempts to con Osomatsu, Choromatsu, and Chibita out of their hard-earned money at his fishing pond with a rare fish that gives them all their money back if caught. / Chibita plays the role of the leader of a gang of thieves who target Osomatsu for discovering their misdeeds.
Episode 3
Totoko's grandpa enlists the help of the sextuplets to stop Chibita and his gang of feral cats from attacking the fish store. / Iyami and Chibita fly around town in a helicopter to cause mischief amongst the locals.
Episode 4
A housework robot (shaped like Chibita) causes havoc amongst the Matsuno family when he malfunctions. / Iyami runs a scam out of a laundromat to catastrophic failure.
Episode 5
Iyami and Chibita feign construction workers to scam the sextuplets out of their money by making a paid shortcut to school. / A camera company offers a cash prize for whoever can photograph a face-making man without any made faces, leading the sextuplets and Chibita to try to claim the reward.
Episode 6
Spooky things seem to be happening around town, leading the sextuplets to discover a secret of their own appearance. / Chibita challenges the brothers to a martial arts battle.
Episode 7
Iyami scams the sextuplets with a magic kettle, actually utilizing Chibita as the secret inside. / Chibita and the shapely-mouthed Bokeo get revenge on the sextuplets for harming their frog friend.
Episode 8
Chibita appears alongside Totoko wearing a strange hat that, when removed, changes his temperament from good to bad, leading to chaos amongst the Matsunos. / Chibita goes boar hunting and encounters the sextuplets and Iyami.
Episode 9
Osomatsu visits dentist Iyami's office for a toothache, but due to an unpaid bill, assists him in fixing up the mouth of Dekapan's crocodilian "son". / After Chibita's mosquito colony is destroyed by the sextuplets, he and Iyami create a watermelon-shaped bomb to enact revenge.
Episode 10
Chibita, with the help of his scientist uncle, devise a plan to shrink the sextuplets down to flea size so that he will no longer be shorter than them. / A roaming minstrel and Chibita team up to enact revenge on the sextuplets with their army of cats.
Episode 11
A wealthy couple pay the sextuplets' parents to loan one of their boys out to them as a paid son, but the love they have for Osomatsu and Choromatsu is much too young for them. / Chibita and the brothers drink an invisibility potion and cause mischief.
Episode 12
A new girl moves into the neighborhood, and the sextuplets try to put the moves on her while confusing her dad for their eerily-resembling dog. / A crime family that Chibita is a part of has business with the sextuplets, climaxing in a rainy nighttime brawl.
Episode 13
An apple-headed doctor conducts an experiment on the sextuplets, but his seemingly strange mood swings are more than meets the eye. / Iyami works as a bespoke clothing designer for the Matsunos, but suspicions are aroused when the family's Children's Day koinobori goes missing.
Episode 14
Ninjutsu master Iyami enlists the help of his disciples Chibita and Moguramaru to get revenge on the sextuplets. / Chibita attempts to thwart Totoko's run as Class President.
Episode 15
Chibita takes the place of Dekapan's trained dog "son" when ringmaster Iyami buys him for his circus. / A student with a padlocked hat transfers to the sextuplets' school, leading to a mystery of his identity.
Episode 16
The Matsunos take a trip in a wacky inventor's time machine to the age of the dinosaurs, where they meet their friends' prehistoric counterparts. / Neighbors Iyami and Chibita go to war with the Matsunos over trash disposal.
Episode 17
Chibita falls in love with snooty Chikako, but the sextuplets' faulty attempts at woo cause more than trouble for the little lovebirds. / The sextuplets watch over a sleepwalking boy who becomes violent when awoken.
Episode 18
A Santa Claus-like figure arrives in the town, in actuality a persona put on by burglar Moguramaru to hide stolen goods. / Deranged dentist Chibita enacts periodontal violence against people with better teeth than him.
Episode 19
The sextuplets become victims of a vindictive clothesless Chibita, who tries to steal their clean clothes. / The Matsunos offer Dekapan a place for his pig "daughter" to stay, but Chibita falls in love with her without knowing she isn't human.
Episode 20
The sextuplets' father invites work friend Iyami over for dinner, but chaos ensues in response to his disruptive behavior. / Chibita attempts to sneak onto an ocean liner under the guise of a sailor.
Episode 21
Iyami runs a "genuine" French restaurant with Chibita, and receives criticism for his poor service and lack of research. / Mr. Matsuno resigns from his position as patriarch, and runs away.
Episode 22
Ultra-rich Iyami accidentally breaks his bejeweled dentures, so with the help of his assistant Chibita, he tries to pin the blame on the sextuplets. / Chibita's army of cats ransack the town's oden vendors of his most favorite food, leading Iyami and the sextuplets to take him out.
Episode 23
A mynah bird settles into the sextuplets' birdhouse village, but is harboring a less-than-desired guest in its home. / Chibita becomes a foster mother for a foundling.
Episode 24
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Episode 25
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Episode 26
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Episode 27
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Episode 28
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Episode 29
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Episode 30
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Episode 31
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Episode 32
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Episode 33
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Episode 34
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Episode 35
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Episode 36
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Episode 37
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Episode 38
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Episode 39
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Episode 40
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Episode 41
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Episode 42
Safecracker Chibita, released on parole, mustn't break into another safe or else he'll be back behind bars. But what will happen when he must use his talents to save a life?
Episode 43
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Episode 44
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Episode 45
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Episode 46
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Episode 47
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Episode 48
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Episode 49
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Episode 50
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Episode 51
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Episode 52
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Episode 53
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Episode 54
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Episode 55
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Episode 56
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Episode 57
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Episode 58
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Episode 59
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Episode 60
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