Tommy and Tuppence Beresford mysteries
Just after World War I, Tommy Beresford and Tuppence Cowley are desperately short of money.
With a shortage of job opportunities, they form a partnership, hiring themselves out as "young adventurers, willing to do anything, go anywhere." In their first dangerous assignment, they must use all their ingenuity to save not only their own lives but also the life of a mysterious girl.
The girl in the photograph has been missing for five years.
...Tommy and Tuppence Beresford, Agatha Christie's delightful sleuthing duo, investigate the strange and troubling doings behind the scenes at a gothic British nursing home in By the Pricking of My Thumbs
When Tommy and Tuppence visit an elderly aunt in her gothic nursing home, they think nothing of her mistrust of the doctors; after all, Ada is a very difficult old lady.
But when Mrs. Lockett mentions a poisoned mushroom
...