Marcia Muller and Bill Pronzini: Double (USA 1995)

From the Publisher:
MYSTERY WAS THE ONLY THING THEY HAD IN COMMON. BUT THAT WAS MORE THAN ENOUGH...
Sharon McCone had come home again: to her warm, troubled family, to San Diego and a convention of private detectives in a posh seaside hotel. For Sharon it was a chance to catch up with old friends. All except for the one who fell four stories from one of the hotel spires.

Now Sharon is determined to find out why her friend, the director of security at the Casa del Rey Hotel, died. To do it she recruits a slouching fellow she affectionately calls "Wolf." Wolf-otherwise known as the Nameless Detective-has uncovered a little mystery of his own at the Casa del Rey. Now the two cases, like the two sleuths, are bonding beautifully -- within a knot of kinky sex and multiple murder that will take twice the cunning to unravel, and twice the luck to survive...

''Nameless' and McCone are a duo who make beautiful mystery music together." -- Atlanta Journal & Constitution
'They double our pleasure... A team that is as memorable as Nick and Nora Charles.' -- San Francisco Chronicle

Marcia Muller and Bill Pronzini: Double. Sharon McCone and the "Nameless Detective". The Mysterious Press published by Warner Books, ISBN: 0446404136 (September, 1995), 294 p., $5.50.

Bill Pronzini & Marcia Muller: Double (USA 1984)

From the Publisher:
In Double, the "Nameless Detective" and Sharon McCone -- reunited at a private eye convention in sunny San Diego-team up to tangle with kinky lifestyles, double dealing and multiple murder. When Elaine Picard, head of security at the posh Casa del Rey hotel and an old friend of Sharon's, falls to her death from a hotel tower, "Nameless" is a distant witness. And when McCone's zealous pursuit of clues lands her in jail, it's "Nameless" who posts bail. While Sharon continues to risk her life trying to unravel the mystery of Elaine's death, "Nameless" puts his own on the line investigating the odd disappearance of a little boy and his mother who've vanished from the Casa del Rey without a trace. The two detectives are swiftly drawn into a treacherous maze of past duplicity and present danger.

The action races from the Casa del Rey to an ominous menagerie in the hills outside of town, a pornographic curio shop, a political campaige headquarters, a villa on the Mexican seacoast, and an isolated desert mansion with a strange history that belies its even more bizarre current goings on.

Double is a crackling and complex thriller from two premier mystery writers.

Bill Pronzini & Marcia Muller: Double. A "Nameless Detective" & Sharon McCone Mystery. St. Martin's Press, ISBN: 0312218079 (October, 1984), 294 p., $13.95.