When Alex was a child his eccentric aunt gave him a ring and told him that one day he should go jump in a lake. He never knew what to make of that, and never tried doing it, until one day at college, he tries to rescue his drunken professor from falling in a river. They both plunge in... and come up in a very different river, in a land that reminds Alex very much of the stories his aunt used to tell: a world like old adventure books and silent movie serials. It's a dream come true, except that his drunken old professor gets himself lost and arrested. Alex must find and rescue him, and return him home, before the old fool gets shot as a spy.