By the notes of Fiáth Pompeiusz, the one-time friend of Kapa and Pepe, Professor Szirtes has solved the secret of the time machine, and he realizes the invention relying on "special" H2O. Kapa and Pepe shall return by it into the past in order to set time right, which is out of joint, that is, to correct history, to save King Louis II, and prevent the Mohács Disaster. Pepe yields to the not too tender persuasion to enter upon the great journey through time, dies and revives, and they arrive at the battlefield of Mohács in time. Kapa films the events. The Turks win and cut off the king's, Pepe's, head, still the Hungarians dictate the peace treaty. Kapa and Pepe want to return, they fill the time machine up with water from the well, yet it won't start. Even so Kapa and Pepe hover over Budapest and quarrel.