As listed in the original script: Demetrius has just taken over the throne (as an impostor who is impersonating the dead son of the last king) and he has married Marina.
The play begins in celebration of the marriage and Demetrius tells his subjects that he forgives everyone who supported the previous king and he will grant every request on this day.
Demetrius is openly attracted to Zarrianna, and he commands her to attend Marina in the palace until the time of the wedding.
Zueski is horrified at the notion of Zarrianna staying near Demetrius, but she assures him that she will be loyal to him and she will not succumb to sexual assault.
Zueski in fact saw the real Demetrius die of wounds and witnessed the burial, but he did not want to be the sole voice to discover the current usurper's identity in what seemed to be a time of national unity.
The king of Poland and the Vaivode (Manzeck) helped to orchestrate the arrival of the impostor Demetrius; Boris was killed by the invading army; the gates of Moscow were opened to the impostor; the wife and sons of Boris were killed; Zueski took Zarrianna away to a monastery for safety.
Zueski points out that he is now the nearest kin to the late Basivolitz and he will speak out against Demetrius with Sophia's help.
Basilius, Zaporjus, and Rureck suspect that Demetrius is an impostor and a tyrant, and they plan to gain the support of Sophia and the public before taking action.
Demetrius' tyranny increases and he plans to divorce Marina, and threatens to cut off her head if she doesn't quietly obey and leave.
Manzeck encounters Alexander and deeply regrets his actions, finally realizing that Demetrius is a usurper.
News reaches Demetrius that doom is impending and he plans to rape Zarrianna, promising to hand Mariana over to Carclos.
Carclos goes to Marina and Zarrianna in disguise, and they agree to follow to see Zueski, Alexander, and Manzeck.
Zueski, Alexander, and Manzeck arrive just as the women call for help from Providence, and they kill Demetrius and Carclos.
The lovers are reunited (Alexander and Marina; Zueski and Zarrianna), and Manzeck blesses his daughter's new union.
The people assert that they will follow Zueski as their new rightful ruler as long as Sophia agrees that Demetrius was an impostor; she does so.