Hook
A regional grocery chain's loyalty algorithm is so accurate that it stops predicting what customers will buy and starts predicting when they will die — the tell is a specific 11-item basket (soft foods, adult wipes, a birthday card bought three weeks early) that shows up an average of 71 days before a cardholder's final transaction. Nobody notices until an analyst named Priya, tasked with cutting coupon waste, builds a dashboard that ranks households by "remaining lifetime value" and realizes the number is literal.
Escalation
- Legal won't let her publish, but marketing loves it: the chain quietly launches "Comfort Rewards," auto-mailing flagged households vouchers for the exact things the dying buy — thickened juice, a folding shower stool, funeral-flower discounts from a partner florist — framed as thoughtful personalization. Redemption rates are the best in company history, because grieving families keep the vouchers like keepsakes.
- A hospice nurse in Dunmore starts using the coupon booklets as an intake tool — if the store mailed the stool voucher, she books the family a conversation — and word spreads through church groups that the supermarket knows before the doctors do. People begin swapping cards on purpose: healthy sons scanning their mother's number so the algorithm sees fruit and running gels instead of Ensure, trying to buy her time.
- The card-swapping poisons the model. Priya's system begins flagging the wrong households — a 34-year-old with a toddler, a man who only ever buys birdseed — and the vouchers land like death sentences, until one flagged customer, humiliated in the checkout line by a coupon for incontinence pads, kills himself. Now the algorithm is right for the wrong reason, and its accuracy ticks up.
- Corporate's fix is elegant and monstrous: stop mailing anything, and instead sell the flag as a B2B feed. Pre-need funeral plots, reverse mortgages, and a cremation startup all buy access. Priya, trying to build a case, pulls the raw scores and finds her own household in the top decile — and the basket that triggered it isn't hers. It's her husband's, bought at a store two counties over, on a card he registered under her name six months ago.
✦ Twist
He hasn't been sick. He's been shopping the death basket on purpose — soft foods, wipes, the early birthday card — for a woman in that town who is actually dying, and who has no insurance, no card, no way to get the Comfort Rewards discounts that make the last weeks affordable. He's been laundering his mistress's dying through his wife's loyalty number. The algorithm didn't predict a death; it caught an affair, and it was right about both.
💡 The engine is a mundane surveillance system that is accidentally *correct*, so every human attempt to game it — swapping cards, hiding illness, buying compassion at a discount — feeds it better data and makes it crueler, until the protagonist discovers the one thing the model saw that she didn't.