The action takes place back in the 9th century - a time of trouble and constant changes. The central dramatic character is that of Constantine the Philosopher -a thinker, a diplomat and a man of letters. He becomes aware of the seeds of destruction in the flourishing Byzantine civilization and senses the future role of Slav Dom. Long before the advance of the Renaissance he becomes convinced about essential equality of people, irrespective of their language and nationality. However, the vine of philosophy is often laced with the poison of politics. Cunning statesmen think of Constantine simply as a weapon in their hands, but they are soon to realize that they have been tragically deceived. The philosopher and humanist towers high above their immediate practical goals. His literary work gets out of the control of politicians. The alphabet intended as a weapon against the young nation proves to be its strength. Together with his brother Methodius, Constantine created the Slav alphabet, which precipitated the development of Slav culture. The film is happy combination of impressive set pieces and artistic taste as it recreates this historical period.