When the world's top scientists suddenly go missing, it's up to Clover, Alex, and Sam to figure out what's behind the disappearing act before it's too late. With the clock ticking, the spies cross time and space, leading to none other than...the Middle Ages! There, they uncover a diabolical plan to annihilate the present--doomsday style! Will our heroines thwart the time bandit's evil scheme? And more important, will they make it back in time for the school's Halloween contest?