Erza, Natsu, Lucy, Gray, and Happy have all returned from the mission to Galuna Island and are greeted by Mirajane. Erza learns that Makarov is not there to punish the others for their actions and Natsu, Gray, and Happy are relieved and Lucy keeps wondering and worrying about that. After Wakaba makes a comment and makes Natsu and Gray mad, they start fighting.
Later, Natsu notices a strange request on the job board. All they have to do is figure out the meaning of the ancient writing and they will earn 500,000 Jewels. Natsu recognizes the words and reads them aloud. Suddenly a strange light engulfs he, Lucy, Erza, Gray, Happy, and Loke. After the light disappears, they all start acting strangely and figure out what has happened. They have switched minds and bodies. Natsu is now in Loke's body while Loke is in Natsu's body. Gray is in Lucy's body while Lucy is in Gray's body. Erza is in Happy's body and Happy is in Erza's body. Everyone is in shock and confused. Loke in Natsu's body sees Lucy, not realizing that it is Gray in her body, screams and runs out. Makarov arrives shortly thereafter and tells them that it is a Changeling spell and they must figure out a way to reverse it within 30 minutes of when it was cast.
Loke is out wandering the streets and sees two girls and goes up to them to ask them out but they run away and he wonders why until he sees that he is drooling fire. He panics and runs back to Fairy Tail.
The others continue to try and figure out what to do and Erza is very depressed to be in Happy's body and this causes many funny scenes since Happy doesn't mind being in Erza's body. Levy, Jet, and Droy arrive and Levy offers to help cure them. They are happy and excited and believe that she can break the spell. As Jet and Droy cheer her on (they are later joined by Elfman), she tries to read up and discover a cure. After several false hopes, she thinks that she's finally found it and reads the spell backwards. A bright light occurs and Lucy and Gray are back to normal and they thank Levy. However, the others are still the same and now Mirajane and Makarov have switched places along with Elfman and Kana. Jet and Droy have also switched places but it didn't make that much difference with them. Levy feels that the situation is beyond her expertise as everyone starts to panic.