Dr. Two-Brains is a major antagonist in WordGirl. Originally known as Professor Steven Boxleitner, a kind-hearted but distracted scientist, he was turned into the evil Dr. Two-Brains after a botched experiment left his mind merged with an evil lab mouse known as Squeaky. He now spends his time coming up with ways to appease his second mind's hunger and urges, but will make sure to cause as much trouble as possible while doing so.