Bicycle Looking for a Whale

Eun Chul and Eun Ha live in a small village. They are the only family they have. One day, stubborn Eun Ha begins to beg Eun Chul to go and see a whale. Eun Ha follows Eun Chul all day long and keeps talking about the whale. To quiet her, Eun Chul makes a false promise.
Eun Ha has a disease which is eroding her vision. Adults tell them that Eun Ha should be sent to a good facility, but Eun Chul can't separate from his sister. Eun Chul decides to show a whale to Eun Ha before she loses her vision completely. They begin to travel from Namwon to Jangsaeng, where they can see a whale. They travel there by bicycle. Along the way to Jangsaeng, Eun Chul and Eun Ha meet Duk Soo. Eun Chul and Eun Ha have warm feelings towards him, like the father they never had...