Cait – from Time Out Bookstore – gave us her a list of standalone mysteries.
They are really clever puzzles with very satisfying endings.
The Song of Seven
by Tonke Dragt
The Westing Game
by Ellen Raskin
York
by Laura Ruby
Clementine Loves Red
by Krystyna Boglar
From the Mixed Up Files of Mrs. Basil E. Frankweiler
by E.L. Konigsburg