|Season 1, Episode 13|
|Air date||July 10, 2007|
With Marcello and Hugo in hot pursuit, Ester, Polvina and Tubarina set off to find a monster octopus they've heard exists.
The girls are watching Marcello and Hugo seemingly acting silly. They decide to ask them what they are doing, at which point Polvina manages to deduce that it has something to do with the monster octopus. She was told that there was someone who had seen the monster, but they didn’t have any proof because it apparently disappears like it was never there. Deciding to find that proof for himself, Marcello takes Hugo to find the monster. Belittled, Ester and Tubarina decide to set off as well, despite Polvina’s insistence that it doesn’t exist.
The boys and girls arrive at the location where the monster was apparently spotted. After a brief conflict, Polvina suddenly decides that they should work together to find it. Hugo and Ester agree, but Marcello and Tubarina don’t. Polvina is about to give up and head home when Hugo sees a baby octopus. Polvina introduces herself to him, but Marcello scares him away.
Everyone pursues the baby octopus. The boys get ahead of them and chase it to a cave. They attempt to move the rocks, but this causes more rocks to fall. Marcello pulls Hugo inside the cave, causing them to be stuck inside. After failing to move the rocks, the girls head off to get help. They spot the baby octopus again, only for it to swim down into another cave. Suddenly, it gets dark; there is a monster octopus caving over them. The girls try to run, but the octopus catches them in her tentacles. Polvina manages to calm her down just as the baby octopus arrives; she was actually looking for him and she thought that they may have hurt him.
The monster octopus apologises for what happened. Realising that they still need to save the boys, the girls decide to have her move the rocks. It is revealed that the cave is actually their home; the monster octopus is able to “disappear” by going back into its cave, with the big rock hiding the entrance. Tubarina realises that they can be famous, but Polvina tells her and Ester that they can’t let anyone know about the monster octopus’ existence because everyone would want to stare and gawk at her and her baby. Tubarina accepts this and the girls agree to her it a secret. They have the boys close their eyes as the monster octopus moves the rocks, while pretending that they are the ones moving it. Marcello and Hugo are freed without them seeing the monster octopus.
As they return home, Marcello reveals to the others that the monster octopus doesn’t exist and that he was just trying to have some fun with the girls. Marcello heads off to tell the other boys and Hugo follows, albeit reluctantly. Tubarina says that they can’t let him get away with spreading lies about them, but Polvina and Ester say that they have to, otherwise they would know about the monster octopus’ existence.