This is the second mystery with Superintendent Battle and Lady Eileen Brent (Bundle). Of all Christie's female characters, I like Bundle the most. Fun, feisty and daring - she's the most engaging youthful character in all of Christie's books.
A group of friends staying in the country set eight alarm clocks to wake up a chronically oversleeping friend... this sets in motion murder, conspiracy and a race for Bundle to find the seven dials and stop whatever dastardly plans they have for England.