Watermelon Island Arc

The  is the 42nd story arc of the Ranma ½ manga, spanning three chapter. It was included as part of Volume 19 of the  and volume 17 of the Viz Media tankōbon.

Plot Summary
The Saotomes and Tendos head to the beach once again and Ranma receives a letter of challenge from Kuno. While waiting, Kuno washes up on the shore in front of Ranma with a watermelon on his head. Kuno appears to have amnesia and does not recognize anyone. However, his personality hasn't changed, and still lusts after the "pig-tailed girl" and Akane. He is also able to flawlessly slice watermelons into many pieces almost instantly. Ranma attempts to jog his memory by hitting him with a watermelon, but he starts chasing Ranma asking for a date. Unable to transform properly into a guy, she swims out to the Watermelon Island with Kuno close behind. Once on the island, Kuno continues to pursue her. Meanwhile, Akane comes to help and triggers a special watermelon training. Ranma sees this and knocks Kuno out with one of the watermelons. When he comes to, Kuno regains his memory and tells Ranma that the challenge letter was actually a love letter written to "the pig-tailed girl".

Major Events

 * Kuno gets amnesia.
 * Kuno acquires a new skill specialized in slicing watermelons.
 * Kuno and Ranma become stranded on Watermelon Island.

Changes in anime

 * In the anime there was no letter challenge from Kuno, Ranma just happened to be on a beach.
 * Kuno chasing female Ranma is a bit shorter (skips hot springs and rain)

Characters Introduced

 * No characters were introduced in this arc