Act I

In the opening act of The Tower, scene i unfolds at the foot of the imposing tower, where the tragic tale of Sigismund, King Basilius's son, begins. Cast into the solitary confines of the tower due to a foreboding prophecy that foretold his revolt against his father, Sigismund has reached the age of twenty-one, oblivious to his royal lineage. He languishes in captivity, treated more like a beast than a prince, relentlessly mocked by his captors. Julian, the governor of the tower, summons a physician to evaluate Sigismund, who observes a regal grace despite his savage life. In scene 2, within a somber room in the tower, Julian confides in the physician the grim details: Sigismund was falsely accused of murder and condemned to die at the tender age of twelve without a fair trial. Hidden with a peasant family until he turned sixteen, Sigismund was then imprisoned in the tower to shield him from assassination. Julian plots with the physician to procure a sedative potion to safely transport Sigismund to a monastery, rewarding the physician with a hefty purse and a precious ring for his aid.

Act II

Scene I of Act II shifts to the serene cloisters of a monastery, where King Basilius arrives with his entourage to converse with the venerable Brother Ignatius, the grand almoner. The king reveals the ominous prophecy to the wise priest, who scolds him for his actions, provoking the king's ire and resulting in the priest's removal. Julian enters the scene, persuading the king to grant Sigismund a retrial to assess his suitability as the rightful heir. The king, acknowledging Julian's unwavering loyalty over twenty-two years, consents to the retrial. Scene ii transitions back to a room in the tower, where Sigismund is reunited with the peasant woman who raised him. She shares the sad news of his stepfather’s death and offers prayers alongside him. Julian then administers the potion, rendering Sigismund unconscious, paving the way for his covert relocation.

Act III

In Act III, the setting is the somber death chamber of the queen. A rejuvenated Sigismund arrives gallantly on horseback, as the king finally acknowledges him as his heir. However, the reunion turns violent as Sigismund attacks the king until attendants intervene. The king, seeing the prophecy fulfilled, declares that his son has indeed rebelled against him. Consequently, he condemns Sigismund and Julian to death for their treasonous acts.

Act IV

The dramatic narrative continues in the castle's grand hall in Act IV, the backdrop for the impending execution of Sigismund and Julian. As Sigismund is marched through the streets towards his fate, a rebellion ignites, overthrowing the king. Sigismund seizes the throne amid the chaos, only to learn that the peasants, led by a man named Oliver, refuse to accept his rule and are in open revolt.

Act V

In the climactic Act V, the scene is set in an antechamber of the castle, where the wounded Julian, victim of the rebels' wrath, is brought before Sigismund, mere moments from death. Oliver, now at the helm of the uprising, confronts Sigismund, challenging his authority. His followers confirm the assassination of King Basilius, and Oliver declares his dominance over the people. In a final act of treachery, Sigismund is shot by Oliver's men and dies cradled in the arms of Anton and the physician, bringing his turbulent saga to a tragic close.