Anna is a 12 year old girl who is very quiet and distant from her foster parents ( Yoriko and her husband) because she found out that her parents get money from the government for looking after her, Yoriko is worried about her behaviour at school. One day Anna was in a class drawing a playground but she has an asthma attack and her foster parents send her to Setsu and Kiyomasa ( relatives of Yoriko) for the summer, Yoriko's relatives live in a seaside town where the air is fresh and clean which could help her asthma.

Anna sees an abandoned mansion across the salt marsh, investigating the mansion, she's wondering why she recognises its. The tide rises and Anna is trapped, Toichi (old, local fisherman) rows her back, Anna looks back at the mansion and for a second all the lights were on. When Anna is back at the Oiwa's, they tell her that the mansion was a vacation home for foreigners but it has been abandoned for along time. That night, Anna dreamed that a blonde girl was having her hair brushed in the mansion. 

On the night of the festival, Anna and Nobuko are fighting about Anna's blue eyes and how she can't explain how she has them as she doesn't know her biological family. Running away, Anna finds a rowing boat on the marsh and rows to the marsh house but the broke breaks and she can't control it. A young blonde girl ask her to throw the rope and help her get tot he mansion. Anna tells Marnie that she saw her in her dreams, Marnie assured her that it wasn't a dream, they both promise to keep there friendship a secret and that they will visit the next evening.

The next evening, Marnie invites Anna to a Party but she is introduced as a flower girl in front of the guest, Marnie danced with a boy ( Kazuhiro). Locals find Anna asleep by the post office and take her back to the Oiwa's. Anna returns to the mansion the next day but the mansion was empty.

1 week later,  Anna was sketching by the marsh where she meets Hisako , who likes drawing the marsh house, she mentions to Anna that the her drawing reminds her of someone she knew. hisako tells Anna that a new family are moving in and the mansion

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