Mid Previa is the grandson of Cid Previa in Final Fantasy V. Cid raised him after his father died in an experiment three years prior to the events of the game. He looks up to Cid, who taught him to never quit, and became as interested in science as Cid himself.
He is first met in the Library of the Ancients, where the books have become possessed. Bartz, Lenna, Galuf, and Faris fight the monster Byblos while Mid is reading a book, and does not seem to notice.
However, when Cid blames himself for destroying the Fire Crystal, Mid is stunned to hear that his grandfather has given up on science, and knocks some sense into him. Together, the two of them become a formidable team, by combining their intellect. When the party finds the airship, they enlist the help of Mid and Cid to rebuild it. Together, they get the airship running again.
In the Merged World, Cid and Mid continue to help Bartz implement a submarine function to the airship. Krile and Mid show their concern for each other before the party leaves the Catapult.
At the end of the game, Mid receives a letter from Krile. The letter states how she misses everyone, since they have all moved on.