The Man with Two Wives — Patrick Quentin

A chance meeting with an ex throws a man's current marriage into turmoil, from the author “in the very first line of detective-story writers” (Sphere).
 
On the surface, Bill Harding has landed on his feet. After failing as a writer and having his first wife desert him and their son, he remarried into a family of wealth and power. His “perfect” new wife is renowned for her charity work, and her father's publishing empire provides Bill with a job, a ritzy Manhattan apartment, and a glamorous lifestyle.
 
All is well until Bill runs into his beautiful ex. Though she's in a sorry state, Bill pushes the thought of her out of his mind. The last thing he expects is to see her again, but her sordid life soon creeps into his rarefied world, bringing with it murder.
 
Now, the more steps Bill takes to protect himself and his marriage, the more the truth is obscured. Bill's own shortcomings come to light, as well as the secrets of a dysfunctional family. With Det. Timothy Trant on the case, Bill must make a decision that could ruin everything -- and strip away the lies that have engulfed them all . . .
 
“This is a fine mid-century detective novel, the essence of a page turning thriller, but one which neglects neither clueing nor characterization.” -- The Passing Tramp 
 
“Svelte.” -- Kirkus Reviews
 
The basis for the 1967 Japanese film Tsuma Futari (“Two Wives”), directed by Yasuzo Masamura