At the request of Her Majesty’s government, private enquiry
agent Cyrus Barker agrees to take on his least favorite kind
of assignment—he’s to provide security for a secret
conference with the French government. The conference is to
take place on the private estate of Lord Hargrave on a
remote island off the coast of Cornwall. The goal of the
conference is the negotiation of a new treaty with France.
The cover story for the gathering is a house party—an
attempt to introduce Lord Hargrave’s two unmarried sons to
potential mates.
But shortly after the parties land at the island, Lord
Hargrave is killed by a sniper shot, and the French
ambassador’s head of security is found stabbed to death. The
only means of egress from the island—a boat—has been sent
away, and the means of signaling for help has been
destroyed. Trapped in a manor house with no way of escape,
Cyrus Barker and his assistant, Thomas Llewelyn, must
uncover which among them is the killer before the next
victim falls.