During the retreat of the Czech army from Bavaria, the rear guard in Mühldorf is under siege. Oldřich from Chlum also fights in it. The knights manage to fight their way to freedom, but even though they should be celebrating, their commanders Smil from Lichtemburk and Vok from Rožmberk are nervous. Soon after, Smil invites Oldřich to his Lichnice castle, where the wedding of his second-born son is to take place. When Oldrich arrives at the castle, he realizes that something is wrong. As wedding guests, there are all those with whom he recently found himself under siege. Even the wedding preparations do not go smoothly, as a violent argument occurs between the betrothed. Oldřich from Chlum watches this with annoyance, but before he can understand what is actually happening, the first murder occurs.