My rating: 5 of 5 stars
The widow is an attractive young woman whose recently deceased husband left her an impregnable box containing unknown objects of incalculable value to be sold in Florida for $200,000. A hefty chunk of change for 1956. Narrator Burt Keating gets involved for a little romance and a cut of the sale and soon finds out that there are dangerous complications since ruthless criminals will do anything to get that box. I loved the 1950s Florida locations - lost forever to development, and the exceptional plotting where attempts to hide and open the mysterious box takes center stage. Some cat-and-mouse action and a couple of heart-stopping twists round out this superb thriller. Robert Colby is one of my favorite writers and this is one of his best. Highly recommended.
The Ace Double is tough to find. Affordable ebooks are available.