It is 1900. Grenfell Lorry is the son of wealthy American parents. On a train in New England Lorry meets a mysterious young woman, Miss Guggenslocker, and finds himself irresistibly attracted. Soon he is following her across the ocean to Graustark, a small, remote mid-European kingdom threatened from within and without by power-hungry schemers who will stop at nothing to become its next rulers. Here, he discovers Miss Guggenslocker is actually the princess of Graustark, and the object of many of these schemes. When the two meet again, they both fall in love. Unfortunately, impoverished Graustark owes money to a nearby country it can not repay, and the princess must marry its prince in order to repay the debt. Otherwise, Graustark will lose half its land and its people will become serfs under their cruel new rulers. Surrounded by spies, the news of Grenfell Lorry's love for the princess becomes known and he is challenged to duels, framed for murder and banished from the kingdom. Fortunately, Lorry does not know the meaning of fear, was a fencing champion in college, and is willing to dare anything for love.