 The cossacks stationed at the fortress defect to the forces of Pugachev, and he takes the fortress easily.He demands that Captain Mironov swear an oath of allegiance to him, and when refused, hangs the Captain and kills his wife.When it is Pyotr's turn, Shvabrin suddenly appears to have defected as well, and upon his advice Pugachev orders Pyotr to be hanged.