A non super-powered character gets superpowers. However, because Status Quo Is God, those powers won't last long and are strictly a one-shot deal. In other words: not only do the superpowers wear off by the end of the episode, but they can never get the powers again. Unless they do using a Recycled Script and/or just because it's fun.
Often happens to the superpowered character's Muggle Best [...] [tvtropes.org]