The Conservatoire is a Paris museum whose galleries become the setting for the novel’s final confrontation. For Casaubon, it is at once a building to investigate, a refuge in which to hide, and the place where the historical patterns he has helped invent acquire lethal consequences. Its power lies in the collision between the museum’s material objects and the stories projected onto them: Casaubon moves through actual halls and cases while imagining the arrival of the Masters, then witnesses a real clandestine assembly beneath the Pendulum.

The Museum and Its Conspiratorial Meaning

Casaubon’s theory of a centuries-long Templar Plan takes a decisive turn after he visits Tomar in Portugal. The castle of the Knights of Christ appears to him to fit the first meeting place named in the Provins message: a location where surviving Templars might have enjoyed protection and contact with another group. He returns with his mind ablaze, persuaded that the Plan began at Tomar and that its references to castles should be read as literal geography. The Conservatoire, already associated with the Pendulum and with the possibility of secret meetings, becomes the destination toward which this reconstruction points.

The museum’s significance is inseparable from Casaubon’s own contribution to the theory. He reminds himself that the aim is not to discover the Templars’ secret but to construct it. Yet the distinction grows unstable: once he has treated Tomar as evidence and imagined a sequence of hidden meetings, the Conservatoire can seem to confirm the Plan he and his companions fabricated. The building does not simply contain a conspiracy; it becomes the physical framework through which Casaubon’s interpretation makes one appear to exist.

A Political Memory Recalled at the Museum

The Conservatoire’s later role is shadowed by Casaubon’s memory of a march against fascist conspiracies in Milan. The march began at the university and brought left-wing intellectuals into a city divided by tacit territorial boundaries: protesters occupied the area beyond Largo Augusto, while fascists were entrenched around Piazza San Babila. Police watched an unpermitted demonstration so long as neither side crossed those boundaries. Casaubon stood among the reporters, editors, and artists near Piazza Santo Stefano rather than marching with a group.

Looking back from the museum, he questions whether he stayed away because the conflict was not his generation’s or because he was avoiding risk. He wonders whether he attended to make himself undergo a test of the decisive moment, and recognizes the contradiction in seeking out a contrived opportunity to prove he would have acted rightly in a genuine one. His later act of entering the Conservatoire is therefore charged with more than curiosity: in Belbo’s apartment, at six on Saturday morning, June 23, Casaubon decides that he cannot ignore the possibility of an event that night. He later recalls that curiosity, and perhaps duty and friendship, overcame fear.

The Nighttime Interior

Casaubon first waits in a small observation post, listening to the building’s creaks and rustles and trying to persuade himself that old cupboards, window frames, plaster, and walls account for the sounds. As the night advances, he decides that any gathering will occur in the nave before the Pendulum and that he must move to a better hiding place. The museum’s display cases and machinery, seen in intermittent flashlight beams, turn familiar exhibits into obstacles and potential sources of noise. In the darkness he imagines another presence matching his movements, a suspicion that reflects how thoroughly the Plan has shaped his expectations.

Near midnight, Casaubon descends a staircase and crosses the Lavoisier Hall and the corridor containing model trains. He sees dim lights moving in the nave and hears people shuffling and dragging objects. Close to the statue of Gramme, he finds that the front panel of its cubic pedestal has been lowered like a gangplank. A man emerges from the concealed passage carrying a gas lantern with colored glass; another joins him from the choir and urges haste, saying that the others will arrive within an hour. The hidden entrance converts the museum from a space of imagined access into a literal route for a clandestine assembly.

The Assembly Before the Pendulum

The gathering takes shape in the nave and ambulatory, with the elect facing the Pendulum and the faithful standing in the nave. Aglie enters in a blue pinstripe suit, leading Lorenza Pellegrini by the hand. Pale, dazed, and dressed in a white semitransparent tunic, she is brought to a brazier near the statue of Pascal. Aglie caresses her face, signals to the Geants d’Avalon to support her, then sits at a table facing the assembly.

Aglie explains that the meeting should have taken place on the night of June 23, 1945, and claims that the group has spent six hundred years in error before finding someone who knows. He calls for Colonel Ardenti, whose disappearance had remained unresolved, and says that the prisoner has named him as the source of his knowledge. Ardenti appears, still recognizable but now unsteady, and is held at a distance by the Pendulum as the gathering turns toward a tribunal. In the Conservatoire, the Plan’s invented history has become an occasion for accusation and danger; the museum’s symbolic center marks the boundary between the assembled group and the man it interrogates.