Several young friends are separated when the Turks attack Vienna in 1683. How each meets the grueling tests of war comprises the substance of the story. Franz and Caspar, the two trumpeter choir boys, contribute to the ""war effort"" significantly, Franz as a messenger and sentry, Caspar as companion to Father Balthasar. A most frightening adventure befalls Maria when she is captured by the Grand Vizier, but with Christian liberation, the friends are happily reunited. A somewhat repetitious and tangled plot is redeemed by graphic battle scenes and a lively picture of the times.