"Go! Go! Itsutsugo Land" centers around the daily lives of five quintuplet siblings—Ichika, Nika, Sanka, Yonka, and Goka—who live together in a small, bustling town. Each sibling has a distinct personality and set of interests, which often leads to humorous and heartwarming interactions as they navigate their shared experiences. Ichika, the eldest, is responsible and often takes on a leadership role, while Nika is energetic and mischievous. Sanka is the most studious and reserved, Yonka is artistic and creative, and Goka, the youngest, is curious and playful.

The series explores the siblings' adventures as they engage in various activities, from school events and family outings to imaginative games and challenges. Their interactions with each other and the people around them highlight themes of family bonds, teamwork, and individuality. The quintuplets often find themselves in amusing situations, whether they are competing in a local festival, helping a neighbor, or simply trying to outdo one another in their daily routines.

Supporting characters, such as their parents, teachers, and friends, add depth to the narrative by providing additional perspectives and contributing to the siblings' growth. The parents, though often busy with work, play a supportive role in the quintuplets' lives, offering guidance and encouragement. Friends and classmates occasionally join the siblings in their escapades, further enriching the dynamic of the story.

The episodic structure of the series allows for a variety of self-contained stories, each focusing on different aspects of the siblings' lives. These stories range from lighthearted and comedic to moments of reflection and personal discovery. Through their shared experiences, the quintuplets learn valuable lessons about cooperation, empathy, and the importance of family. The series balances humor and warmth, creating an engaging portrayal of childhood and sibling relationships.