Anastasia and Edward Upston are summoned to the Order of Time's London headquarters to provide testimony. Their friend and mentor Dr. Alfred Gregorian has been charged with violating the time-traveling society's rules in relation to their trip to ancient Egypt. The twelve-year-old twins are determined to defend Dr. G and to get a closer look at the inner workings of the Order and its secret academy.

Their trip to London doesn't go according to plan when the twins unexpectedly find themselves stuck a thousand years in the past during the Viking Age. Getting home becomes secondary when they are caught in the midst of a power struggle between Odin and Loki that could instigate the end of the nine realms. Surviving long enough for Dr. G and the Order to rescue them may be the hardest thing they ever do. If they can ....