A woman tells him that her husband’s father was killed when he was run over by a tram three years ago. He writes down the basics of her story, and she tells him that she’s embarrassed by the story because her father, who was a Buddhist priest, had been drunk and passed out on the tram lines.

He asks her why she’s come to see him and she says it’s because her husband, who works as a stockbroker at Merrill Lynch, has refused to take over his father’s position as priest. After the death, her mother-in-law moved into the apartment below them and began having panic attacks. When these come on, she calls the woman and her husband and they come down to be with her. One day, her husband had gone down to be with his mother and asked his wife to have breakfast ready for when he came back. But, when he didn’t come home, she called her mother-in-law, she informed her that her husband had left a long time ago. Her husband did not come home and hasn’t been seen since. She tells him that her husband always takes the stairs because he’s afraid of the elevator and then asks if he’ll take her case. 

He accepts the investigation into her husband's disappearance and says he’ll do it for free because he’s a volunteer detective. The woman takes him to her apartment building and shows him the wide and lighted staircases that her husband frequented. She says that since her husband’s disappearance, her mother-in-law’s nerves have taken a turn for the worse. He tells her to tell the building supervisor he is carrying out an insurance investigation, so as not to arouse suspicion. 

The first thing he does is walk the stairs between the mother-in-law’s floor and the couple’s floor. On the 25th floor, the mother-in-law’s floor, there was a lounge and the detective stopped and rested on the sofa after going up and down the stairs three times. On a Sunday afternoon, he passes a man who’s running up the stairs who told him he runs up the stairs and takes the lift down every day. The runner said he knew the disappeared man and has seen him on the lounge sofa. He says there are a lot of people in the building who are afraid of the elevator and that several other runners use the stairs to workout. 

On Tuesday, he was sitting on the sofa when he saw an old man walking down the stairs. The old man smoked in the lounge and said it’s a daily habit. The man also says he knows the missing husband and that he usually sits on the lounge sofa and stares off into space. After two more weeks, he stumbled across a young girl in the lounge who was singing into the mirror. She tells him she lives two floors above and always takes the stairs down to this lounge because it has the best mirror. When he looks in the mirror, he finds he looks happier and plumper, as though he’s eaten a full stack of pancakes.

The girl questions him to see if he’s creepy and when he tells her unprompted that he doesn’t collect girls’ underpants, she decides to trust him. When she asks him what he’s looking for, he tells her a door that he’s been searching for since before she was born. On Saturday morning, his client calls and tells him her husband’s been found, sleeping in a waiting room in Sendai Station. He has no idea how he got there and is wearing the same thing he was when he went missing. His last memory is leaving his mother’s apartment and beginning his ascent up the stairwell. He wrote down the details she provided on his memo pad and stared at the ceiling. Aloud, he welcomed the man back to the real world and imagines his next case.