"Lassie" is a manga adaptation of the classic story of a loyal and intelligent Rough Collie dog named Lassie, originally created by Eric Knight. The manga retells the timeless tale of Lassie's unwavering devotion to her human companions, blending adventure, emotion, and themes of loyalty and perseverance. The narrative centers on Lassie's journey to reunite with her family, showcasing her intelligence, bravery, and deep bond with those she loves.

The story begins with Lassie living with a young boy named Joe Carraclough and his family in a small village in Yorkshire, England. The Carracloughs are a working-class family, and Lassie is not just a pet but a cherished member of their household. However, financial difficulties force the family to sell Lassie to the wealthy Duke of Rudling, who takes her to his estate in Scotland. Despite the distance, Lassie's loyalty to Joe drives her to escape and embark on a perilous journey back home. Along the way, she encounters various challenges, including harsh weather, dangerous terrain, and encounters with both kind and hostile individuals.

Lassie's journey is marked by her resourcefulness and determination. She navigates through forests, crosses rivers, and evades capture, all while maintaining her focus on returning to Joe. Her interactions with other characters, such as a kind-hearted elderly couple and a group of travelers, highlight her ability to inspire compassion and forge connections. Meanwhile, Joe and his family grapple with their loss, holding onto hope that Lassie will find her way back to them.

The manga captures the emotional depth of Lassie's bond with Joe, emphasizing themes of love, loyalty, and the enduring connection between humans and animals. The narrative also explores the socio-economic struggles of the Carraclough family, adding a layer of realism to the story. The Duke of Rudling, initially portrayed as a stern and distant figure, undergoes a transformation as he witnesses Lassie's determination, ultimately recognizing the depth of her loyalty.

Through its episodic structure, the manga highlights Lassie's adventures and the impact she has on those she meets. The story culminates in a heartfelt reunion between Lassie and Joe, underscoring the power of perseverance and the unbreakable bond between them. The manga remains faithful to the spirit of the original story, offering a poignant and engaging retelling of Lassie's timeless tale.