Seo-jin is a widower still grieving his wife's death. Then he receives the news that his long-lost younger sister, Yoo-jin, who went missing 25 years ago, has turned up. Unlike the rest of his family, who welcome her into their arms, Seo-jin feels that Yoo-jin is a stranger.

Intruder

Hyunji approaches a man with the bait of a survey. The man continues to talk and eventually expresses his interest in Hyunji's seemingly suspicious but pitiful attitude. The moment you think Hyunji's intentions worked, the man makes another suggestion to Hyunji, and Hyunji listens to the man. Nothing is easy. In a world of deceit and deception, nothing comes without a price. The tension rises.