The Case of the Missing Lady — Agatha Christie

When a six-foot-tall tan giant of man comes into Albert Blunt's International Detective agency, Tommy and Tuppence -- married couple and detective aficionados -- are in for a treat. Not only has Mr. Stavansson emerged after a two-year Arctic adventure, but he's lost his fiancée Hermione too. What telegrams and scraps of information Tommy and Tuppence can gather are all the hope the adventurer has in finding her. But this information leads the duo into dangerous situations, investigating secluded country houses in the dead of night, and that's only the start of it….