Arthur and Linus depart Marsyas by train under stormy skies, saying goodbye to the children and extracting promises of good behavior while Zoe and Mayor Helen watch over them. Sal pulls Arthur aside to insist the children will listen to Arthur’s upcoming testimony on the radio, arguing they have the right to know what is being said about them. Arthur agrees, asking that Zoe and Helen help them process it, and reassures Sal that adoption and family are not limited by age. As the train pulls away, Arthur leans out the window to shout his love, shaken by how hard it is to leave.

They arrive in the rainy, noisy city, and Linus insists on a bus ride before the hotel. He takes Arthur to Hermes Way, to his former home at 86 Hermes Way, where Linus admits the place once contained the life he used to have. Linus explains he is selling the property once Mrs. Klapper’s nephew returns to finalize the purchase, but first Linus needs to keep a promise.

In the front flower beds, Linus scatters enchanted seeds given by Phee and Talia. The seeds burrow into the soil, magic surges, and the ground trembles as vivid flowers erupt in seconds, transforming the drab yard with bright blooms and an enormous sunflower. The display reminds Arthur of the children’s power and leaves him admitting his nerves about what is coming, while Linus confesses he is frightened too and encourages Arthur to proceed anyway.

That evening, they ride back toward the hotel and Arthur spots an old newspaper featuring his younger face with the headline “WHO IS ARTHUR PARNASSUS?” and mention of his “landmark testimony,” prompting him to move away from it. They stay at The Rose & Thorne near Bandycross, eat takeaway, and call home, letting each child recount their day; Chauncey asks eagerly about meeting David, the yeti, and Arthur promises to report back after he has met him.

After the call, Linus discovers a listening device hidden in the bathroom light fixture and realizes someone arranged their room to spy on them. Instead of fleeing immediately, Arthur proposes giving the eavesdroppers “a show”: he invites Linus to dance to the radio, insisting they choose joy over fear on the eve of testimony. They sway together, and Arthur whispers that the listeners can learn what joy sounds like.