"Lupin III: The Pursuit of Harimao's Treasure" is a feature-length anime special that centers on the legendary thief Arsène Lupin III and his team as they become entangled in a high-stakes quest for a fabled treasure tied to historical intrigue. The narrative begins with Lupin and his associates—Jigen, Goemon, and Fujiko—receiving a cryptic message about the Harimao Treasure, a vast fortune hidden by a British officer during World War II. The treasure is said to be linked to a secret Nazi project, making it a target for multiple factions, including a rogue British intelligence officer, a powerful crime syndicate, and a mysterious figure known as Harimao.

The story unfolds as Lupin and his team race against these adversaries to uncover the treasure's location. Their journey takes them across Europe, from London to the Balkans, where they encounter a series of elaborate traps, double-crosses, and historical revelations. Along the way, the group uncovers the truth about Harimao, a former resistance fighter who has his own reasons for seeking the treasure. The narrative weaves together elements of espionage, historical conspiracy, and the classic Lupin III formula of heists and humor.

Key characters include Lupin, whose cunning and resourcefulness drive the plot; Jigen, his sharpshooting partner; Goemon, a master swordsman with a strong sense of honor; and Fujiko, whose loyalties remain ambiguous as she navigates her own agenda. Inspector Zenigata, Lupin's perennial pursuer, also plays a significant role, adding tension and comedic relief as he attempts to apprehend Lupin while inadvertently aiding his quest. The antagonists, including the enigmatic Harimao and the ruthless crime syndicate, provide formidable challenges, each with their own motivations tied to the treasure's legacy.

The plot is structured around a series of escalating heists and confrontations, culminating in a climactic showdown where the true nature of the Harimao Treasure is revealed. The story balances action, intrigue, and character dynamics, staying true to the Lupin III franchise's signature blend of adventure and wit. Historical references and geopolitical undertones add depth to the narrative, grounding the fantastical elements in a recognizable world. The special maintains a brisk pace, ensuring that the stakes remain high and the audience remains engaged throughout the treasure hunt.