Set in the Edo period of Japan, a young maiden must free her 12 brothers from a curse by their wicked stepmother that turned them into whooper swans. The only way to break the curse is that she must make 12 shirts made by nettle and Hakonechloa macra (Japanese grass). However, in order for the spell to work, she must not speak, cry, nor laugh, nor show any emotion while she is making the shirts. Luckily, she has a friend who is engaged to her oldest brother, before he got turned into a swan, so that she'll do the speaking for her.
Meanwhile, a young prince was wandering the forest when he saw the young maiden making the shirts. So far, she has only made three and her friend often changes the bandages on her hands because the cuts the grass keeps making. She also makes sure that the maiden still manages to bathe, eat, and sleep. The prince took pity on her and asked if she would like to stay in his palace, but her friend has one acceptation, if they can bring her 12 swan brothers and let her continue to finish making the shirts. The prince agrees and takes her and the swans home with him.
