Strangled in the Sauna

Why do the owners of fabulous jewels refuse to have the police called in when they are stolen? How could a thief open a bedroom safe? Dodie has an aversion to exercise - and even more to massage. But she is persuaded to go to the Yorkshire health spa by Elena whose boy friend is cousin to the owners. Suspicion obviously falls on the maids but other staff have legitimate reasons to visit guest rooms. But how they dispose of such well-known jewels? Then a murder and the plot thickens.