Shinji Konuma works for a small apparel maker as a sales rep. One day on his way to the Metro that runs beneath the streets of Tokyo, he passes through a time warp that takes him from the 1990s back to 1964, when the city is caught up in the hoopla surrounding the Olympic Games. There he comes upon his older brother Shoichi, who committed suicide under the pressure of his college entrance exams. Though completely at a loss as to how he got there, Shinji attempts to stop his brother from killing himself . . .
At entrances to Metro stations all over Tokyo, or in the underground passages leading to the subways, or sometimes in a moving subway car, Shinji repeatedly slips back and forth between the present and the past. Accompanying him on his time travels is Michiko Karube, a woman from his workplace. Shinji has a wife and family, but without revealing their pasts to each other, the two become romantically involved. Each slip back in time stretches a little farther than the last. After Shinji's encounter with his brother, he comes upon his father Sakichi, from whom he has been estranged for 30 years. Sakichi had ultimately achieved great success as an entrepreneur, but Shinji now sees his father in the immediate postwar period, clawing his way up from the rubble by boldly grabbing every opportunity that knocks and building a future for himself. In his youth, Shinji had rebelled against his father and left home, but now he comes to regard this earlier Sakichi with growing admiration. The past is a source of unexpected, eye-opening truths. On his final trip back in time, Shinji is stunned to learn that Michiko is in fact his half-sister. But then, when he returns to the present world the following day, he discovers that Michiko never existed . . .
Tunneling through time by way of the subway system, the tale offers a vivid and nostalgic portrayal of Japanese society as it was in the eras before and after World War II, while also deftly shining light on complex love-hate relationships within the family. The work brought author Jiro Asada his first major award, and helped establish his reputation as a writer of novels that move readers to tears.