"Detective Conan: Sunflowers of Inferno" is a feature-length anime film based on the popular "Detective Conan" series. The narrative centers on Conan Edogawa, a high school detective trapped in a child's body, as he investigates a high-stakes art heist tied to a series of cryptic clues involving Vincent van Gogh's paintings. The story begins when a valuable painting, "Sunflowers," is stolen from a museum in Tokyo. The theft is linked to a mysterious organization, and Conan, along with his friends and allies, becomes embroiled in a dangerous quest to recover the artwork.

The plot unfolds as Conan deciphers a series of riddles left by the thieves, leading him to Kyoto, where the trail intertwines with historical art and hidden messages. The investigation reveals connections to a larger conspiracy involving international art smugglers and a secretive group with ties to the criminal underworld. Alongside Conan, characters such as Ran Mouri, Kogoro Mouri, and the Detective Boys play pivotal roles in unraveling the mystery. The narrative also introduces new characters, including art experts and law enforcement officials, who provide critical insights into the case.

As the story progresses, Conan uncovers the true motive behind the theft, which involves a hidden treasure linked to van Gogh's works. The film builds tension through a series of action-packed sequences, including chases, confrontations, and narrow escapes, as Conan races against time to prevent the stolen art from falling into the wrong hands. The climax takes place in a dramatic setting, where the final pieces of the puzzle come together, revealing the mastermind behind the heist and their ultimate goal.

The film maintains a balance between mystery, adventure, and character-driven moments, staying true to the tone of the "Detective Conan" series. It explores themes of art, history, and the lengths to which individuals will go for personal gain or preservation of cultural heritage. The narrative concludes with the resolution of the case, though it leaves room for the ongoing challenges faced by Conan and his allies in their fight against crime.