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Tae-suk (JAE Hee) drifts around on his motorcycle looking for empty houses to stay in. He goes from door to door and puts up flyers in the keyholes of each house. He later breaks into the house where the flyer has not been removed, assuming that the owner is away.
Tae-suk lives in the empty house until the owners return, but never steals or ruins anything. He simply guards the houses for a few days, fixing broken items, and even does the owners' laundry. Before leaving, he puts everything back as it used be.

One day, sneaking into a wealthy home, Tae-suk meets his destiny – a married woman named Sun-hwa (LEE Seung-yeon) who has been tormented by her abusive husband. While Tae-suk sneaks around the house, Sun-hwa hides in the dark and silently watches him. At first she's afraid of him, but when she sees him fixing a broken scale, she realizes he's not a thief and continues to observe him.

That same night, Tae-suk wakes up suddenly to find Sun-hwa staring at him. He runs out, but the phone rings suddenly. It's Sun-hwa's husband. Tae-suk overhears their conversation and realizes that Sun-hwa has an unhappy marriage and life. Sun-hwa looks silently at him as if she is begging for him to save her. Tae-suk however, turns away and walks out.

Tae-suk can't stop thinking about Sun-hwa's imploring eyes. The more he tries to forget about her, the more vivid the images of Sun-hwa become in his mind. Tae-suk sneaks into her home again, and watches her in silence. After watching her for a while, Tae-suk turns on music to soothe her soul. He prepares clothes for her while she's in her bath. Sun-hwa senses that Tae-suk has come back for her and starts to feel comfortable. But her comfort turns sour after her husband comes home and tries to force her into having sex.
Tae-suk is enraged. He grabs a 3 iron and swings it at golf balls on the ground. The balls strike her husband several times and he collapses. Tae-suk then runs away with Sun-hwa.

Together, Tae-suk and Sun-hwa stick flyers onto doors and enter empty houses together. In every home they break into, Tae-suk continues to cook, do chores, and fix broken items. For the first time ever, Sun-hwa feels the real comfort of a home. Tae-suk sees that she is able to smile again, and the two ultimately fall in love with each other.

One day, as they enter a house, they discover the dead body of an old man. Tae-suk and Sun-hwa bury the body in a respectful ritual, and begin living in the old man's house as if it was their own. Their happy days come to an end when the old man's son makes a surprise visit. He calls the police and they take Tae-suk and Sun-hwa away.
Tae-suk is charged with murder, trespassing, and kidnapping, while Sun-hwa is unwillingly brought back to her husband. Sun-hwa lives in hope for the day of Tae-suk's release. But while in prison, Tae-suk finds a secret way to bring back the joys he and Sun-hwa once had...