A sonic boom and a flash of blue light announce the arrival of CHAOS in the Lexington household! How come the Lexingtons' foreign exchange student arrives in the middle of the night without a suitcase, wearing stinky tights, and carrying a sword? How come he doesn't know what a bathroom is? As usual, Mr. and Mrs. Lexington are totally clueless. But Josh and Katie are on the case. Could Jack Bradford really be from the year 1599? And if he is, what's going to happen when Josh and Katie bring this swashbuckling teen to school? Welcome to Time Flyers, where the past meets the present and the present is changed forever.