Marco arrives at Mr. Barris’s London office for an appointment and finds it in chaos as Barris packs to leave the city, with crates and blueprints piled everywhere. Marco asks directly how much Barris knows, specifically what Miss Bowen has told him. Barris confirms Celia revealed the competition only in broad terms and admits he now realizes Marco is her opponent.

Barris explains his role as an engineer who helps make real magic look like plausible construction, which Celia calls “grounding.” He clarifies that the Stargazer is purely mechanical, though he suspects Celia helps keep it functioning. Marco tests the situation by noting he could erase Barris’s memory, but Barris insists he can remain neutral, keep confidences, and assist either competitor without taking sides; Marco accepts and asks for Barris’s help with an unspecified task.

Later, Barris receives a letter from Celia and worries she will react badly to his increased knowledge, or demand her opponent’s identity. Instead, her note only asks, “May I make additions to it?” Barris replies that the design was made to be manipulated by either side, inviting her to add whatever she wishes.

Celia moves through a sequence of interconnected rooms: a snowy hallway with many doors, a chamber where books hang in frozen cascades, and then a glittering white desert beneath a star-filled sky painted on the walls. In the starry space, her father confronts her, condemning the “debauched” proximity of their work and warning that collaborating is improper. Celia argues that competing within the same tent is clever and points out she does not even know her opponent’s identity, questioning how a winner can be judged when their creations blur together.

Prospero presses Celia to do more, calling her a disappointment; Celia protests that greater effort is exhausting and asks when it will ever be enough. When he gives no answer, she is left alone among the stars, sitting in the pearl-white sand. Elsewhere, Marco works alone in his flat, building tiny paper rooms, halls, doors, and stairs that connect into Celia’s spaces, deliberately leaving openings for her to respond—turning the contest into a continuing, shared architecture.