Triangle by Danielle Steel

As she approaches the milestone birthday of forty, delicate beauty Amanda Delanoe finds joy in running a chic contemporary art gallery in Paris. With the companionship of her dog, Lulu, and her friend and co-owner of the gallery, fun-loving bachelor Pascal Leblanc, Amanda lives well, but so far the love of her life has eluded her.

Then she meets Olivier Saint Albin, a handsome, enigmatic publisher. At the same time, she reconnects with Tom Quinlan, an old boyfriend from her university days, who has come to Paris to devote himself to writing a thriller. Amanda’s attraction to Olivier is instant, but she soon learns he is married, leaving her torn between her head and her heart.

Amanda’s situation is further complicated by the unpleasant feeling that she’s being watched. When she begins to receive threatening phone calls late at night, and someone breaks into her apartment on the Left Bank, it’s all too clear she is in real danger. But from whom?

An old love, a new love, or a stranger? As love enters her life, so does terror. . .