Someone has given Dorry the Giant exploding ale and he's not happy! Assuming it was Luffy and crew, he launches an all-out attack and is soundly defeated by the rubbery power of the Gum-Gum Rocket! But mystery is afoot--if Luffy didn't slip the giant the exploding brew, who did?

Nami's sick! Now the Merry Go is without her navigator! Luffy and crew have but one choice--find land and hopefully a doctor. They miraculously stumble upon Drum Island, where it is eternally winter, but upon arriving they find out the island has only one medical professional--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!