Alone atop Petřín Tower, Robert Langdon braces against the wind and replays the “blank” email image Katherine sent earlier: a screenshot of her phone showing seven Enochian characters. Langdon recognizes the symbols as Enochian, the so-called “Angelic Tongue” associated with Prague mystics John Dee and Edward Kelley.

Langdon remembers telling Katherine about Enochian the previous day after they saw an exhibit poster featuring the symbols, and he recalls downloading an Enochian translation app onto Katherine’s phone as a joke. Now, with Katherine missing, Langdon concludes she likely used the app to create a secret message and sent him the screenshot.

Using his memorized Enochian key, Langdon transliterates the symbols into English letters, but the result—“LXXEDOC”—seems meaningless. He worries Katherine may have mistranslated the message without realizing it, leaving him with no usable lead.

Searching for his next move, Langdon watches a huge flock of birds rise and turn in perfect unison, which triggers a memory of Katherine explaining behavioral synchronization as evidence of an invisible interconnection among living things. He recalls her telling Jonas Faukman that separation is an illusion, citing experiments and an Einstein quote about the “optical delusion” of disconnectedness, and hinting that her own results could transform humanity’s understanding of reality.

A piercing squeal snaps Langdon back to the present as a black ÚZSI sedan skids to a stop at the tower’s base. A muscle-bound uniformed man leaps out and sprints toward the tower with a pistol in hand, signaling imminent danger for Langdon.