A British couple, Patrick and Thomasina Tobin from Greenwich, south-east London, were found dead naked beside the hot tub of a luxury cliff-top villa in Cullera, near Valencia, in the early hours of 25 August, while on a two-week family holiday. The case has attracted widespread attention because the couple's two teenage children, both of whom have special needs, were present at the property, and because investigators and experts have struggled to agree on how the deaths occurred, despite ruling out foul play.

Initial tests indicate both died of cardiopulmonary arrest, though the exact cause is still unconfirmed, and theories have ranged from electrocution and chemical poisoning to overheating or drug use. Police have suggested the pair may have become trapped by a malfunctioning suction mechanism in the tub, with minor injuries hinting at a struggle or rescue attempt, but spa technician Francisco Quero and Carlos Navarro, chief executive of Goccia Spa, which sold a hot tub to the villa in 2019, have both dismissed this theory as implausible for an adult, with Navarro also disputing that the tub shown in recent images is even the one his firm supplied.