Quirky 12-year-old Noelle Hawkins may be one of the brightest girls in her class but even she is completely miffed to explain how her dad, wacky scientist Big Brain Brian, spontaneously combusted while sitting in a portaloo. It's true that he was working on a new top secret Brain Ray machine and was on the point of a great break-through – could this have had something to do with his disappearance? With the help of her sister Holly, Noelle is determined to find out what really happened to her dad!