Police in Lancashire are hunting burglars who are thought to have used the homeowners' hot tub before stealing £3,500 worth of items from the house.
The thieves struck at a house in Orchard Drive, Oswaldtwistle, between 0130 and 0200 GMT on Monday.
A neighbour raised the alarm after hearing a disturbance in his garden. He saw his hot tub and the one next door had been uncovered.
Police believe the neighbours fled when he knocked on the front door.
Sgt Simon Holderness, of Lancashire Police, said the thieves got into the detached house through the conservatory door, which had been left unlocked, while the owners slept upstairs.
They stole a Nintendo Wii, laptop, television, mobile phones, handbag and cameras.
The couple's neighbour told police he believed people had been using his hot tub in recent weeks.
Sgt Holderness said he could not confirm whether the burglars had taken a dip, but said the hot tubs had clearly been "interfered with".
He said he could not recollect such an unusual incident in his 20-year career as a police officer.
Sgt Holderness added: "Although there is a bit of entertainment value to this story, a family have been left out of pocket at a difficult time of year.
"We are taking it very seriously."
He advised homeowners to ensure all doors and windows were locked, to have security lighting and to install and use home alarms.