In the lively streets of Japan, an unusual vigilante rises, cloaked in secrecy. K (Shinji Takeda), a talented young debugger and programmer during the day, morphs into a formidable figure by night, administering justice to wrongdoers with a meticulous strategy that ensures they remain unscathed. This cryptic individual has adopted a distinctive ritual: donning thick glasses prior to each shooting—an eccentricity that has earned him the media nickname "Four-eyes" (or Le Bigleux in its original form).
Meanwhile, Hinano Yoshikawa, a curious 17-year-old hairdresser, unwittingly becomes entangled in a fascinating enigma. One day while riding the subway, she witnesses a young man covertly filming the other passengers, prompting her to track him down with the assistance of her friend Naomi (Kaori Mizushima). Their investigative journey leads them to K, and as they strike up an unexpected friendship, Hinano finds herself immersed in the exhilarating world of trance music and video games that K experiences.
As their connection deepens, Hinano becomes aware of K's nighttime pursuits, witnessing one of his non-lethal altercations firsthand. This revelation ignites a moral quandary for her, leading to a frank discussion with K. He unveils the fact that he has altered his pistol to be inaccurate, ensuring that the bullets do not strike their intended victims. Yet, a later event takes a darker twist when K mistakenly shoots a man breaking up with his girlfriend for someone else.
In a revealing moment, K explains the real reason for his glasses: they act as a psychological tether, enabling him to maintain emotional distance and avoid eye contact with his targets. This unique method stems from his aspiration to capture the surrounding world through video footage rather than merely observing it. As K shares this pivotal insight with Hinano, he expresses a desire to forsake his vigilante persona, effectively distancing himself from "Four-eyes," thus offering some relief to Hinano.
However, K's isolated life is soon disrupted by an unexpected encounter with a minor yakuza member (played by Beat Takeshi), raising the tension when a gun, borrowed for uncertain reasons, inadvertently discharges into K's lower abdomen. Instead of seeking medical help, K decides to brave the agony and meets Hinano, strengthening their bond as they navigate the urban landscape together. Genuinely captivated by Hinano's presence, K invites her to the pinnacle of Tokyo—a magnificent observation deck that appears to soar into the clouds. There, Hinano awaits patiently while K's injury gradually reveals its toll, causing him to stagger dangerously along the edge of a bustling street, as if precariously balanced on the brink of destiny itself.
The film concludes on an intriguingly ambiguous note, leaving viewers pondering whether K has indeed met his end. It is notable, however, that international versions of the film, including the original Japanese cut, include an additional seven minutes of footage that may provide a more resolute resolution to this captivating and thought-provoking narrative.
