"Porfy no Nagai Tabi" is a historical drama anime set in the early 20th century, adapted from the novel "The Long Journey of Porfy" by Paul-Jacques Bonzon. The story centers on Porfy, a young Greek boy, and his younger sister Mina, who are orphaned after their parents are killed during a conflict in their village. The siblings are separated when Porfy is taken to a prison camp, while Mina is adopted by a wealthy French family. Determined to reunite with his sister, Porfy escapes the camp and embarks on a perilous journey across Europe.

Porfy's quest takes him through various countries, including Greece, Italy, and France, as he faces numerous challenges, including poverty, exploitation, and the lingering effects of war. Along the way, he encounters a diverse cast of characters who either aid or hinder his progress. These include kind-hearted individuals who offer him shelter and guidance, as well as those who seek to take advantage of his vulnerability. Despite the hardships, Porfy remains steadfast in his determination to find Mina, driven by his love for her and his promise to their parents.

Mina, meanwhile, grows up in a privileged environment but remains haunted by memories of her brother and their shared past. Her adoptive family, though caring, is unaware of her inner turmoil and her longing to reconnect with Porfy. The narrative alternates between Porfy's journey and Mina's life, gradually building toward their eventual reunion.

The series explores themes of resilience, family bonds, and the impact of war on individuals and communities. It portrays the socio-economic disparities of the time, highlighting the struggles of marginalized groups and the resilience of the human spirit. The characters are shaped by their experiences, with Porfy's unwavering determination and Mina's quiet strength serving as central pillars of the story. The anime's historical setting provides a backdrop for its exploration of universal themes, making it a poignant and emotionally resonant tale.