Absolutely nothing happened in the quiet sleepy town until a sultry, scorching sun hung over it... blue! It would seem that what else can be expected after this, but from that moment on, the poor students deduce ingenious formulas, dogs play chess, and crazy shoes and chairs rush through the streets. And only Peggy Sue knows that all this is the work of invisible ghosts who hate the human race. “How can we save people from the insidious and cruel Invisibles?” - she thinks feverishly, and this is where the ghosts go on a decisive offensive...