English model, photographer, and author of romantic fiction Pat Booth (1943-2009) wrote a book titled The Big Apple (1984). The title was shortened to Big Apple in 1985 and 1992 printings. 
 
The book is described on OCLC WorldCat: “Set in the world of international high-life and the shadowy underworld of bizarre and jaded sex, a tale of ambition, greed and lust in which a good-looking yet highly amoral man’s financial dealings trigger deadly intrigue that threatens a top psychiatrist’s career.”
 
 
Wikipedia: Pat Booth
Pat Booth, Lady Lowe (24 April 1943 – 11 May 2009) was an English model, photographer, and author of romantic fiction.
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Partial bibliography
. Lady and the Champ (1980)
. Rags to Riches (1981)
. Master Photographers: The World’s Great Photographers on Their Art and Technique (1983)
. Self Portrait (1983)
. Sparklers (1983)
. The Big Apple (1984)
 
OCLC WorldCat record
The big apple
Author: Pat Booth
Summary: Set in the world of international high-life and the shadowy underworld of bizarre and jaded sex, a tale of ambition, greed and lust in which a good-looking yet highly amoral man’s financial dealings trigger deadly intrigue that threatens a top psychiatrist’s career. From the author of SPARKLERS and MARRY ME.
Print Book, English, 1984
Publisher: Futura, London, 1984
 
OCLC WorldCat record
Big Apple
Author: Pat Booth
Print Book, English, 1985, ©1984
Publisher: Macdonald, London, 1985, ©1984
     
OCLC WorldCat record
Big apple
Author: Pat Booth
Summary: The glittering novel of money, power and sizzling sex
Print Book, English, 1992, ©1984
Publisher: Warner, London, 1992, ©1984
 
Amazon.com
Big Apple Paperback – April 1, 1992
by Pat Booth (Author)
Paperback
Anne Carrington - beautiful, intelligent, successful: a top psychiatrist with an exclusive New York practice. Adam Phipps - poor little rich boy with the looks of a god, the morals of a sewer rat…and a computer programme that could crack Wall Street. Mariel O’Sullivan - angel-faced bad time girl determined to make Adam her meal-ticket, if she can keep him in the gutter long enough. This explosive trio scorch a trail of passion & depravity across New York & Europe, until Adam’s financial dealings trigger a deadly intrigue that threatens Anne’s career - and Adam’s life. Spanning the glittering world of international high-life and the shadowy underworld of bizarre and jaded sex, BIG APPLE is a searing novel of ambition, greed and lust.