Nakahara Hiroshi is a middle aged Salaryman, who feels disconnected from his wife and children, and is haunted by a sense of existential failure. One early morning, after a night out, he takes the wrong commuter train home and ends up in the suburban town where he spent his early life. On a whim, he decides to visit his mother's grave, and while he prays in front of it, he passes out.
He wakes up feeling oddly different. He's shorter and lighter than he's been in decades. Looking at his reflection, he realizes he has been sent back in time, and he is once again a 14-year-old boy. He must re-adapt to the school and family life of a teenager in the early 1960's, all the while trying to figure out why his father mysteriously disappeared that summer, never to return.
The story was adapted to movie format in 2010 with the French film Quartier Lointain, which moved the setting to 1960's France. Taniguchi got a cameo in it.
Contains examples of:
- Annoying Younger Sibling: Hiroshi's kid sister. As a real teen he got along reasonably well with her, but as an adult in a teen's body he no longer has any patience for her.
- Beach Episode
- Fish out of Temporal Water: The early 1960's were a different time.
- Ill Girl: The childhood friend who Hiroshi's father was secretly visiting.
- Joshikousei: Tomoko.
- Ordinary High-School Student: Inside that 14-year-old's body is the mind of an adult man from 35 years in the future.
- Parental Abandonment: Hiroshi never got over his father's unexplained disappearance.
- Peggy Sue: Hiroshi. He, much like the Trope Namer, returns to his older body with a new book dedicated to him by someone he heavily interacted with him in the past waiting for him at home.
- Pragmatic Adaptation: The film version, while otherwise faithful to the original story, moved the setting to France.
- Set Right What Once Went Wrong: Hiroshi tries to do it, but it's more complicated than it looks.
- Trapped in the Past: Hiroshi is sent back in time to his early teenage years.
- War Is Hell: Hiroshi's father is a World War II vet and went through hell during Japan's Burma campaign.