Bats Fly at Dusk — A.A. Fair

A hot-headed PI's missing person case leads to murder in this mystery by the creator of Perry Mason and author of Owls Don't Blink.
 
Bertha Cool and Donald Lam make for an unlikely pair of private detectives. She's a fifty-something-year-old widow built like a longshoreman with a mouth to match. Donald is a wiry ex-lawyer in his thirties with a face that's a magnet for fists. Fortunately, he's whip-smart. His brains have gotten him and his partner through the toughest of cases. However, with World War II on, he's recently enlisted in the navy, leaving Bertha flying solo with her next client . . .
 
A blind beggar is searching for a young lady who disappeared after being hit by a car. Bertha's certain she can handle a missing person case on her own, especially after her client asks her to break a hundred-dollar bill. But when her search yields murder, Bertha is suddenly flying blind. Now she must quickly locate a killer before everything comes crashing down.
 
“No one has ever matched Gardner for swift, sure exposition.” -- Kirkus Reviews
 
“The best American writer, of course, is Erle Stanley Gardner.” -- Evelyn Waugh