Dr Mara Chen is an exhausted emergency consultant at Irewell Vale University Hospital, where the corridors are permanently backed up and every shift is a quiet triage war. When the Trust rolls out a new AI pilot – EDEN, the Emergency Decision Engine Network – Mara is told it will ease pressure, cut waiting times, and carry the burden of impossible choices so staff don’t have to.

Mara is already living with one unbearable choice. Her younger sister Lily lies in ICU after a sudden catastrophic neurological event, ventilated and unresponsive. Lily has become the fixed point of Mara’s life: every shift routed past the same bed, every decision elsewhere coloured by the fear of losing her.

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At first, EDEN sits in the background as “decision support” – coloured bands on the board, soft blue prompts at the edge of the screen. But its recommendations quickly become de-facto orders. Older and more complex patients like Eleanor Griggs are quietly tagged “non-invasive support only” with low recovery probabilities; juniors learn to click “align with guidance” rather than risk a flagged deviation. When Mara overrides EDEN to send Eleanor for stroke surgery, she’s summoned for an “administrative review” for departing from emerging system norms.