The Old Man says that everything in the Colonel's house belongs to him. "Very well it is yours. But my family escutcheon and my good name remain my own," the Colonel replies. The Old Man refuses, and points out that the family name that the Colonel has been using belongs to a family that has been extinct for a hundred years.
"I have heard rumors to this effect, but I inherited the name from my father," the Colonel says, before reading The Armorial Gazette, which the Old Man presents to him, and realizing that his name in fact does not belong to him. He hands the Old Man his signet ring, defeated, and the Old Man tells him that he is not actually a colonel. "You once held the temporary rank of Colonel in the American Volunteer Fore, but after the war in Cuba and the reorganization of the Army, all such titles were abolished," he says.
The Colonel goes to ring the bell, but the Old Man threatens to have Bengtsson arrested if the Colonel calls him. He notes that the guests are arriving for dinner and tells the Colonel that everyone should "continue to play our old parts for a while." The Colonel recognizes the Old Man, but cannot identify him, when the Student enters. The Colonel introduces the Student to the Old Man, not realizing they know each other. He takes the Student to the Hyacinth Room to talk to the Girl, so that he can finish his conversation with the Old Man.
The Colonel says that the Girl only ever stays in the Hyacinth Room, a peculiarity she has. Suddenly, the Colonel notes the entrance of Miss Beatrice von Holsteinkrona, who the Old Man identifies as his former fiancée. According to the stage directions, the Fiancée looks "a little crazy" as she is introduced to the Old Man, and takes her seat.
The Aristocrat, Baron Skanskorg, enters and is wearing mourning dress. Without rising, the Old Man says in an aside, "That's the jewel-thief, I think." He then tells the Colonel to bring in the Mummy, but leave the Girl and the Student in the Hyacinth Room.
The Old Man launches into a lengthy monologue in which he says, "Silence cannot hide anything—but words can. I read the other day that differences of language originated among savages for the purpose of keeping one tribe's secrets hidden from another. Every language therefore is a code, and he who finds the key can understand every language in the world. But this does not prevent secrets from being exposed without a key, specially when there is a question of paternity to be proved." He tells the group that the Girl is his daughter, and after a long silence says, "That was my mission in this house: to pull up the weeds, to expose the crimes, to settle all accounts, so that those young people might start afresh in this home, which is my gift to them." He says that he will allow everyone to leave when the clock strikes, and everyone who stays will be arrested.
In a moment of silence, the Mummy goes to the clock and stops it, before delivering her own monologue, scolding the Old Man for judging them. "...You are not the one you appear to be. You are a thief of human souls. You stole me once with false promises. You murdered the Consul who was buried today; you strangled him with debts. You have stolen the student, binding him by the pretence of a claim on his father, who never owed you a farthing," she says, before calling in Bengtsson.
The Milkmaid appears in the hall, seen only by the Old Man, then disappears as Bengtsson enters. Bengtsson tells the group that he knows the Old Man, because the Old Man used to be a sponger in his kitchen. As a servant, the Old Man was terrible at his job, and drank the soup stock out of the cooking water, like a vampire, leaving food for his masters that was not nourishing. Years later, Bengtsson saw the Old Man in Hamburg under another name, where he was being charged for having lured a young woman onto some ice to kill her because she knew of his crimes as a usurer, an immoral money lender.
Johansson listens from the hall, "knowing he is now to be freed from slavery." The Mummy opens the cupboard door and invites the Old Man to go in and hang himself with the rope that he used to strangle the Consul and with which he intended to strangle the Colonel. When the Old Man goes inside, Bengtsson puts the death-screen up around the door, and everyone waits.
In the Hyacinth Room, the Girl has a harp "on which she plays a prelude, and then accompanies the Student's recitation," a verse about seeing what is hidden and the fact that no wicked deed goes unpunished.
Scene 3. In the Hyacinth Room, filled with hyacinths. There is also a sitting Buddha statue that has a shallot in his lap, "bearing its globular cluster of white, starlike flowers." The Colonel and the Mummy are sitting in the Round Room, while the Student and the Girl are in the Hyacinth Room. The Girl has her harp and they discuss the fact that they both love hyacinths. The Student says, "I have loved them ever since I was a child, have worshipped them because they have all the fine qualities I lack...And yet...My love is not returned, for these beautiful blossoms hate me."
He tells the legend of the hyacinth, the fact that the flower is "an image of the Cosmos," with a bulb that represents the earth and bursts up into star-flowers which represent the sky. "This poor earth will become a heaven. It is for this that Buddha waits," he says. They relish in their shared love and theorizing about spirituality and flowers. The Student asks the Girl why her parents sit so silently in the Round Room, and she tells him that they have nothing to say to each other.
The Old Man manages to strip the Colonel of all his credentials in one fell swoop. He takes out a newspaper that suggests that the Colonel has no claims to the noble name that he uses, and also makes a case for the fact that he is not a colonel at all. Using his almost magical powers to dissolve the structures around him, the Old Man is able to disenfranchise the powerful Colonel swiftly and suddenly, and get the Colonel to agree to hand over everything that he has.
The narrative of the play follows a revenge plot, akin to a literary classic like The Count of Monte Cristo, in which a wronged man enters the home of his enemy and enacts his revenge. In contrast to this classic formula, however, is the fact that the Old Man, the avenger, is shrouded in mystery and a rather odious reputation. The audience, rather than having a centralized protagonist with whom to identify and sympathize, is led through a moral thicket, a landscape in which it is impossible to know who to trust or what is right.
In his rambling monologue to the assembled guests, the Old Man philosophizes on the nature of language. He suggests that language was invented to obscure the truth, rather than clarify it, and that silence can reveal the truth much more effectively. His reasoning fits into the ghostly logic that pervades the play, the atmosphere of mystery with which Strindberg imbues his text. The Old Man posits that perhaps there are more answers that can come to light in the spaces in between declarations, that there are ghosts that make themselves known in the transitional or liminal moments.
No sooner has the Old Man delivered his claims against the group that has assembled than the Mummy reveals that he is the true villain. With the help of the servant Bengtsson, she exposes the Old Man as a notorious usurer and a man who can literally suck the nourishment out of food. He is the embodiment of selfishness and mercenary acts, and his attempts to frame the other dinner guests as criminals fails when he is exposed as the true criminal.
The relationship between the Student and the Girl could not be more different from the lives and attitudes of the older characters. At the beginning of Scene 3, they stand in the flower-filled Hyacinth Room discussing their mutual adoration for the flowers that surround them, and speculate about the spiritual and symbolic significance of the flowers. They are bubbling over with light and enjoyable conversation, and enjoy an innocent and romantic existence, unsullied like the relationships of their elders.