Ever since the death of her husband, Ursula Ottway has lived alone in Back Rigg Cottage, high up on the fells overlooking the beautiful Crow Water reservoir. She has always been popular in the local community, but Ursula's life is far from secure. Her landlord, the ambitious politician Marcus Grenville, wants his property back, as the cottage would provide a perfect holiday residence for the tourists who come up to shoot on the estate. After months of petty harassment, Ursula discovers that the illegal use of poisoned bait on Grenville's land has killed not only a rare bird of prey but her two beloved cats. And she realises that she can bear no more.

Outraged by this act of cruelty, Ursula storms up to the Grenvilles' house and - to the amazement and horror of the guests gathered for dinner - she denounces Marcus Grenville and threatens revenge. It would hardly look good, after all, for a future government minister to be caught flouting the law on his own land.

But when her niece, Molly Palmer-Jones, arrives at Ursula's house the next morning, it is to find her body slumped lifeless on a sofa.

Shocked and saddened, Molly and her husband George decide to piece together a picture of Ursula's last days. And it soon becomes clear that, for many people on the estate, hers was a very convenient death. The Palmer-Joneses embark on a murder investigation . . . but even their professional expertise doesn't prepare them for what is to follow. Because a lifetime's worth of secrets must surface before a killer can finally be brought to justice . . .