It's Rock Island's Octopus Festival, but there's not an octopus in sight…In an effort to save the festival Taylor and Nori set off to solve the mystery, while Lila is working against the clock to choreograph their festival dance routine.

It's the Institute science fair and Ellis and Taylor discover a mysterious symbex that causes them to swap brains! In order to swap back, they need to solve the puzzle of the symbex and… dive into a shark tank…