After Professor Chakravarti’s departure, the tower’s mood turns bleak. Early camaraderie and busywork give way to long, isolating hours, shortages, and meagre meals. Robin and Victoire remain together in strained companionship, then finally speak about Letty. Robin confesses he believes Letty intentionally shot Ramy, linking her humiliation to her choice. Victoire, torn between anger and pity, offers their old daguerreotype and reflects on Letty’s loneliness and sense of betrayal.

Ibrahim begins a meticulous chronicle of the strike, seeking statements from everyone to counter a hostile future record. Robin recoils at being historicized while still fighting, mourning the erasure of Hermes and Griffin’s unseen work. Victoire agrees to participate, hoping to sway posterity, as Ibrahim jokes they might one day be remembered like the Oxford Martyrs.

Violence escalates outside. Soldiers target individuals; a shot shatters a window near Victoire. Robin recovers a round rimmed with silver, evidence of Playfair-derived munitions that can penetrate Babel’s wards. The realization reframes the action as a siege, not a secure strike, and they resolve to avoid windows while uncertain defenses hold.

Abel’s barricaders fight back, many being veterans. Translators assist: Victoire forges the élan–energy match-pair to boost range and impact of projectiles. Other experiments—seduce and Nachtmahr—fail to yield usable effects. Abel brings rifles and asks to station marksmen in the tower to exploit its vantage.

As cannon fire continues, Abel explains the V-shaped barricades and wagers on a crisis of conscience among soldiers if streets are taken. Inside, they cling to the Saturday ultimatum over Westminster Bridge. Yusuf drafts amnesty terms for a potential settlement, while Robin, unable to imagine an after without Ramy and Griffin, withdraws. On the roof, Victoire insists there must be an after; Robin admits the fight has nonetheless fallen to them.