Ellie Simons's delightful mother-in-law comes to visit for a simply lovely weekend of crocheted doilies, thinly-veiled insults, and passive-aggressive "suggestions."

It's enough to make anyone wish their mother-in-law was dead. But it turns out the ladies of Chitterton Fells should be more careful what they wish for. Only last night Ellie and her friends raised their gin and tonics to toast an end to mothers-in-law the world over . . .

The next day, Pamela Pomeroy's own MIL is found dead. Lady Kitty Pomeroy went over the handlebars of her bike into the village pond and drowned. Was it a horrid accident, or is someone really ridding Chitterton Fells of all the mothers-in-law?

Ellie must catch this killer before her own darling mother-in-law is the next to be bumped off.