Mr. Tendo announces to his three teenage daughters (Kasume, Nabiki, Akane) that one of them is going to have to marry Ranma Saotome the son of his friend Genma Saotome. His daughters are both annoyed and then surprised when Ranma shows up but is a girl instead of a boy and is accompanied by a panda bear.
The three Tendo sisters quickly learn that all is not as it seems. Genma and Ranma were both cursed. Genma is transformed into a panda and Ranma into a female version of himself when they are doused with cold water. They change back to their original forms when they are dowsed with warm or hot water.
Nabiki and Kasume decide that Akane will have to be the one to marry Ranma. Akane has no interest in marrying Ranma. She is a devoted martial artist, like her father, but not at his level or the same level as Genma or Ranma Saotome.
