Synopsis
The story begins, in Austria, at midnight. Park Eun-young is making a wish among a crowd celebrating the New Year.
The scene changes to a young Song Yi-na watching her childhood friend Yoon Jae-ha playing in what seems to be a piano competition. Switching back to present day, Song Yi-na smiles remembering her wonderful memories and promises made. She begins a conversation with the passenger next to her, Park Eun-young. She explains that she is on her way to Austria to meet her childhood love, Jae-ha, after a 15 year separation. Yi-na continues to explain that her first love has become an accomplished pianist as Eun-young explains her excitement about her first trip outside of Korea.
Once in Austria Eun-young bumps into Phillip (Jae-ha’s manager and best friend), who mistakes her as Yi-na whom he planned to pick up at the airport. After the situation clears itself, Eun-young, Yi-na, and Phillip go their separate ways. Phillip takes Yi-na to see Jae-ha. Once at their destination, Jae-ha doesn't recognize Yi-na and mistakes her for a reporter. Yi-na, upset over Jae-ha's cold reception, begins to talk back at him. Jae-ha later hears her name said by Phillip, which he repeats and seems to spark his memory.
While taking Jae-ha and Yi-na out, Phillip sees Eun-young and decides to break company. Phillip introduces himself to Eun-young and offers to help her get around Austria. After learning that she will be in Salzburg the next day, he offers her two concert tickets.
Later that night, Jae-ha is seen looking through photos of himself and Yi-na as children. Putting the photos away, he later pulls out a handmade rainbow shell.
The next day, Eun-young meets Jae-ha on the train ride to Salzburg. Though Jae-ha displays a cold demeanor towards Eun-young, the two are immediately attracted to each other – especially Jae-ha, because of the way she reminds him of his long-lost childhood love, Seo Eun-young. Eun-young offers one of the concert tickets to Jae-ha and introduces herself as Alice. He states that his name is Chris (Chris Y. is his stage name). They become separated once in Salzburg. Eun-young arrives for the concert and meets Phillip, but is eager to see Chris again.
As the concert begins, Eun-young recognizes Chris Y. as the Chris on the train. As the concert concludes, Eun-young begins to leave the hall, but a melody Clementine stops her in her tracks as she begins to recall her childhood past.
15 years ago...
Lee Soo-ho and his father Lee Jung-tae arrive at Jung-tae's hometown, a beautiful island outside of Seoul. They meet Seo Eun-young and her mother. Jung-tae leaves Soo-ho with the mother and daughter, promising to return. Soo-ho, full of hurt and anger, treats Eun-young badly. Soo-ho tries numerous times to escape the island. At one point Eun-young gets caught in his plan and is taken to the hospital. Soo-ho learns that Eun-young is sick and is in need of a special surgery.
Soo-ho and Eun-young become closer; Eun-young presents a rainbow shell she made as a gift. Jung-tae returns to the island and promises Soo-ho that he will finally settle down on the island with him. Soo-ho continues to fear that his father will leave again but hopeful of his father's promise. Later, Soo-ho informs his father of Eun-young's sickness and that her mother must be saving for it. Hearing about money, Jung-tae breaks into the family's room.
Eun-young's mother sees Jung-tae running towards the ferry. Upon returning to her home, she learns that the money she was saving for Eun-young's surgery was stolen. In disbelief and despair, she asks Soo-ho where his father went. Eun-young's mother leaves the island for Seoul in hopes of tracking down Jung-tae. While searching, she is hit by a car and is instantly killed.
Soo-ho, hurt, angry, and full of guilt tries to leave the island again by stealing a boat. Eun-young tries to stop him but ends up going with him. The next morning, the children are swept to a neighboring island where an elderly couple take them in. Soo-ho tries to leave again without Eun-young but to no avail. The two make it to Seoul and begin their search for both parents.
While searching, Eun-young becomes ill and Soo-ho rushes her to the hospital. At the hospital, Soo-ho meets a woman, Hyun Ji-sook, who mistakes him for her son. Desperate for money, he tries to steal a woman's purse. He is stopped from going to jail by Hyun Ji-sook's husband, Yoon Myung-hoon.
Yoon Myung-hoon asks Soo-ho if he would consider pretending to be his son, Jae-ha, until his wife recovers. Soo-ho learns that the couple's son, Yoon Jae-ha, was previously killed in a rafting accident. Soo-ho refuses but reconsiders when he learns that Yoon Myung-hoon has the money to save Eun-young's life.
Eun-young wakes to find Soo-ho at her hospital bedside. Fearing that Soo-ho will leave, she asks that he promise to stay by her. Soo-ho promises but is unable to keep it. The day of the surgery he leaves with the couple. Remembering his promise to Eun-young he runs back to the hospital but finds her room empty. Lee Soo-ho leaves South Korea as Yoon Jae-ha.
Jae-ha is later told that Eun-young died during her surgery. After the surgery, Seo Eun-young recovers and is adopted by her aunt, Jo Yang-soon, changing her name to Park Eun-young.
Present day...
After the concert, Phillip convinces Eun-young to accompany him to the concert's after party. At the party, Jae-ha meets Alice (Eun-young) again, but learns that Phillip is romantically interested in her. Aware of Phillip's past with women, Jae-ha believes that Alice (Eun-young) was toying with him on the train. The next day, Eun-young leaves for the Crystal Palace. She doesn't see Phillip but leaves a "thank you" note and gift, an ornamented seashell. While Phillip and Yi-na observe the details of the shell; Phillip mentions Eun-young's name causing Jae-ha to run after her.
Jae-ha arrives at the Crystal Palace but misses Eun-young. Later Jae-ha agrees to produce an album for Yi-na's music company in Korea and returns after 15 years.
Both Jae-ha and Phillip are looking for Eun-young. Jae-ha is the first to spot Eun-young and traces her to a kimbap restaurant. While in Jo Yang-soon's kimbap restaurant, he comes to the conclusion that this Eun-young is not Seo Eun-young because she refers to the owner and a worker as her mother and brother. Jae-ha leaves the restaurant angry and disappointed. Eun-young notices that the customer left his scarf and didn't pay for his meal. She goes after him and notices that it is Yoon Jae-ha.
Soon after, Phillip locates Eun-young. Eun-young is surprised and then recalls having seen Jae-ha. A few days later, Eun-young is reunited with Phillip, Jae-ha, and Yi-na while making a lunch delivery.
Phillip, interested in Eun-young, begins to follow her in hopes of starting a relationship. Eun-young struggles with providing for her family and tries to find a steady job. Phillip, seeing Eun-young hardships, arranges a job for her with Yi-na's music company as a chauffeur for Jae-ha.
As time passes Eun-young and Jae-ha become closer and begin to develop feelings for each other. Yi-na begins to sense something between the two but tries to ignore her suspicions. Phillip, unaware of Eun-young and Jae-ha's feelings, confesses to Jae-ha that he is falling in love with Eun-young. Listening to his best friend's excitement, Jae-ha is conflicted and begins to push Eun-young away. Eun-young, hurt by Jae-ha's behavior, confronts him. Unable to contain his feelings and seeing Eun-young hurting, Jae-ha kisses her, unaware that Philip sees them from away.
Having confessed their love to each other, Eun-young and Jae-ha continue their relationship in secret.
One day, Eun-young goes to the island where she and Soo-ho grew up together. His adoptive parents had previously told Jae-ha that Seo Eun-young was dead, but he decides to investigate himself. When he meets Eun-young again on the island, he finally realizes that Park Eun-young and Seo Eun-young are one and the same person.
Jae-ha becomes confused whether he must become Soo-ho or Jae-ha. When he speaks this problem aloud at the graveyard of Eun-young's mother, Yi-na hears it and she realizes that the man in front of her is not her childhood sweetheart Jae-ha, but Soo-ho.
As Jae-ha, Eun-young, Yi-na, and Phillip return to Seoul, Jae-ha meets his real father Lee Jung-tae, who left him when he was young. Jung-tae is now a drunkard, and Jae-ha bitterly admits to him that he is Soo-ho. His words are heard by Eun-young and Phillip. Stunned, Eun-young realizes Jae-ha is Soo-ho, her childhood love.
Eun-young is angry because she thinks young Soo-ho left her in the hospital on purpose. In reality, young Soo-ho left to be adopted by Mr. and Mrs. Yoon who paid Eun-young's hospital bill, but Eun-young does not know this fact.
When she finally learns the truth, she goes to find Soo-ho. However, Soo-ho is missing. But Eun-young knows the place where he has gone. The island! So she goes to the island and meets Soo-ho there. There is a happy reunion.
But life becomes complicated as the media discovers Soo-ho's real identity. He must choose whether he wants to go back to being Soo-ho or remain as Jae-ha. In a press conference, Jung-tae arrives to save Soo-ho's career, lying that he is not his son, but is Yoon Jae-ha. Finally Soo-ho declares that he is Jae-ha.
After Jung-tae is killed in a traffic accident, Soo-ho becomes depressed. Before his concert in Korea, he accidentally hurts his own hand by searching for his shell given by young Eun-young in the dustbin, when the a piece of broken glass pierces his hand. But he insists on playing the piano at the concert.
The nerves in Soo-ho's hand become impaired, ending his piano career. He returns to Austria, not letting Eun-young know about his injury.
Nonetheless, Yi-na comes back to Korea and asks Eun-young to marry Soo-ho. Yi-na also tells Eun-young that Soo-ho cannot be a professional pianist anymore due to the paralyzed nerves on his hand. He has lost his sense of touch.
Thus, Eun-young flies to Austria and meets Soo-ho coincidentally on a bridge. Then they get married. Soo-ho buys a house on the island where he and Eun-young grow together. It is the same house they lived in for Soo-ho's recording.
In the ending, it is shown that Soo-ho plays a small piano at a local school. Finally, he and Eun-young dance on the balcony of their house at sunset, and kiss.
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