Windmill Of The Gods by Sidney Sheldon
Mary Ashley, a professor at Kansas State University, is offered an ambassadorship by Paul Ellison, the US president. She rejects the offer because her husband, Dr. Edward Ashley, does not want to leave his medical practice, and she is not willing to be separated from him. She also feels that it is harder to find a good doctor for a small Kansas town than an ambassador to a foreign country. When her husband suddenly dies in a suspicious traffic accident, Ashley accepts the President's offer in order to fill the void in her life. She is sent to Romania, behind the Iron Curtain, where she finds that everyone is conspiring against her. She's on the glinting edge of East-West confrontation, a beautiful and accomplished scholar who has suddenly become the new US ambassador to an Iron Curtain country, a woman who is about to dramatically change the course of world events – if she lives. For Mary Ashley has been marked for death by the world's most proficient and mysterious assassin, and plunged into a nightmare of espionage, kidnapping and terror.