Ep 10. Sgt. Frog Versus the Cavitians of Cavity 9!

In Sgt. Frog season 1 episode 10, titled "Sgt. Frog Versus the Cavitians of Cavity 9!", the members of the Hinata household are up against a new kind of threat - cavities! One by one, they all fall victim to intense toothache, except for Fuyuki who had the foresight to brush his teeth on time. When the Keronian discovered what cavities are, Natsumi brought him to the dentist to have his teeth checked. Before he knows it, he is being strapped into a high-tech dentist's chair and probed with foreign dental tools! Sgt. Frog is so traumatized by the experience that he declares war on the cavities themselves! But when he tries to take on their source - Cavity 9 - are his alien abilities enough to deal with this insidious enemy?

The episode starts with Fuyuki brushing his teeth in the bathroom while Keroro is having a relaxing bath. Fuyuki warns the alien about the gravity of cavities, and how they can be quite painful. This warning comes to fruition when everyone in the Hinata household experiences excruciating toothaches caused by their cavity-infested teeth. Fuyuki, the only one who remembered to brush his teeth, seems to be the only member of the household spared from this affliction.

The group soon learns about the existence of Cavity 9 and that it is the culprit behind their toothaches. Keroro senses a great opportunity to wage a new war on a never-before-seen enemy - cavities! The Keronian sets out to single-handedly take down Cavity 9, much to the surprise of the Hinata family's resident dental expert, Tamama. He warns Keroro of the disastrous path he is about to tread. With his confidence in his abilities and his powerful weapons, Keroro ventures into the underground of the dental clinic.

Once there, Keroro comes face to face with a swarm of microscopic creatures known as Cavitians. They're the ones behind the dreaded affliction that's engulfed the Hinata household. Keroro does not back down from the fight, but he soon realizes that he may be in over his head with these creatures. The Cavitians trap Keroro in an icy prison, leaving him to contemplate his next steps.

Meanwhile, the rest of the troop tries to figure out what's wrong with Keroro. With the help of the ever-resourceful Momoka, they manage to communicate with Keroro using a microphone and speaker system. Once they learn of his predicament, they devise a plan to help him. With Tamama's help, they manage to keep the Cavitians busy while Keroro makes his escape. But even with Tamama's strength, will they be able to survive the onslaught?

Sgt. Frog Versus the Cavitians of Cavity 9! provides a hilarious and thought-provoking lesson on the importance of dental hygiene. Moreover, the episode introduces us to an entirely new concept of enemies that the Keroro Platoon must face. With Keroro's tenacity, Tamama's brute strength, and the rest of the troop's ingenuity, they defeat the hidden enemy. However, it's still unknown if the Hinata household is safe from their new foe and if Keroro would ever visit the dentist again. Ultimately, this episode leaves us all wanting more, and fans are eagerly looking forward to the next one.