This is the first time the Thing is turned back into his human form.
When Sue is abducted she is in a pink dress and when Doom is showing the diplomats he will cause a tidal wave to destroy their cities/countries he warns the FF that he has has their "Heart" (One of his predictions) he shows Sue again in her street clothes/Dress. Lastly when the FF attempt to put an end to Doom he shows Sue in a room trapped she is wearing her FF outfit. When did she have time to change and where did she get her FF outfit from?
Villian: Dr. Doom
Based on "Defeated By Dr. Doom!" from Fantastic Four #17 (August 1963), written by Stan Lee, art by Jack Kirby.