Daniel opens the locked room in the Fortuny apartment with the hidden key. Inside, the space is sealed in darkness and plastered with crucifixes hanging from the ceiling and carved or painted across furniture, mirrors, and tiles. The dust shows fresh footprints around a bare bed and a rolltop desk whose drawers have been forced open and emptied.

Daniel studies notebooks left in the desk: repeated sketches, stray words, exercises, fragments of poems, and fantastical drawings of a rambling house and a man made of flames. A photograph slips out of one notebook, showing the same girl Daniel saw in an earlier picture, posed near the villa called The White Friar on Avenida del Tibidabo. The inscription reads, “Penélope, who loves you”, which Daniel pockets. Before leaving, Doña Aurora admits she kept a letter that arrived soon after Julián left for Paris; Daniel quietly takes that envelope from a cabinet drawer.

That afternoon Daniel visits the building administrator, Mr. Molins, and extracts the name and supposed address of the lawyer handling Sophie Carax’s affairs: José María Requejo. Daniel checks a street guide and discovers the address does not exist, while the mail is allegedly sent to a post office box at the main post office on Vía Layetana (box 2321). Molins then recounts the Fortunys’ history: Antoni Fortuny’s marriage to Sophie Carax, Sophie’s pregnancy by another man, Antoni’s violent religious obsession and abuse, and Julián’s childhood as a gifted, imaginative boy increasingly drawn to art and books, growing up in a house ruled by shame and cruelty.

Back at the bookshop, Fermín tells Daniel that Bea Aguilar stopped by and said she would see Daniel on Friday, prompting Fermín to push Daniel toward her despite Bea’s engagement. With business slow, Daniel sends Fermín off to see Bernarda, but first asks him to discreetly find out who owns PO box 2321 and who collects its mail; Fermín agrees, swearing secrecy from Daniel’s father.

Soon after Fermín leaves, Chief Inspector Francisco Javier Fumero enters the shop and delivers a veiled threat, insulting the watchmaker Don Federico Flaviá and accusing Daniel of employing a notorious thief (clearly referring to Fermín). Fumero warns Daniel that he must choose sides and promises they will meet again, leaving Daniel shaken and unwilling to spread the fear Fumero is trying to plant. Later, unable to sleep, Daniel opens the stolen 1919 letter and reads Penélope Aldaya’s message to Julián: she confirms Julián fled Barcelona, says she is confined and threatened (Jorge swearing to kill Julián), insists she still loves him, and hints at secrets “better you should never know.”