Tesco and its ever-popular Clubcard was once caught up in a terrifying blackmail plot that saw a disturbed customer threaten to put his HIV-infected blood into food.
Back in 1995, a shopper called Frank Riolfo claimed he had the disease and warned he would contaminate the products unless the supermarket created a card to pay him an eye-watering sum of money.
Riolfo told bosses to pay him £250,000 via the plastic card after calling the Tesco store in Kettering, Northamptonshire, calling himself St Mary-Ann.
