One Piece Volume 15

Nami's sick! Now the Merry Go is without her navigator. Luffy and crew have one choice: find land and hopefully a doctor. They stumble upon Drum Island where it is eternally winter, but upon arriving they find out the island has only one doctor - and she's a witch! With Nami's life on the line, Luffy sets out through the snow-laden fields to find this doctor, witch or not!