Locarno

Locarno is the counterpart to the override system at Wortalleth West, linking it to the novel’s central technological threat: Cascade, a chain reaction that can activate nanobots beyond a single host. Its significance lies less in a developed physical portrait than in its role as one of the few places associated with possible control of that process.

The Remote Override

During the inspection of Jack Harkness’s office, the narrator notices tall metal-doored cupboards with ventilation panels and blinking lights. The narrator speculates that the equipment may be backup hard drives powering a relay—an override for the override in Locarno that Filippo Crosetti had described. The observation makes the office’s apparently ordinary computers and storage part of a concealed control infrastructure, while the narrator’s uncertainty leaves the exact function of the equipment unconfirmed.

Locarno and Cascade

The later explanation identifies Locarno as one of two places where overrides can be operated; the other is Wortalleth West. The nanobots are designed to activate in sequence when triggered, passing the signal from one to another within ultrasonic range. Doctor Tau has solved the problem of controlling nanobots from outside a host, and the resulting method is called Cascade. The system at Wortalleth West can initialize it, while the paired overrides offer a limited means of intervention.

Restricted Control and Risk

Knowledge of how to operate the overrides is restricted to Jack Harkness and the speaker explaining the system. The arrangement gives Locarno strategic importance but offers no broad safeguard: without control, the chain reaction cannot be stopped once it begins. The stated trigger is a breach of the panic room at Wortalleth West. Harkness’s plan relies on someone eventually breaking into it and initiating Cascade without realizing what has happened; the people who understand the mechanism expect the effects to become apparent only later. Locarno therefore represents a concealed point of control within a system whose trigger is deliberately hidden from its eventual victims.