Spoiler Alert: The ending of this thriller is revealed in the final paragraph of the summary. The threat of terrorism and the moral code of a physician place Dr. Collin Reeves in a very difficult position. The young American doctor is a specialist in parasitology and tropical diseases. He has trained and worked around the world - London, Kuwait, Brazil, and Africa. He presently practices in Mexico City. The U.S. Embassy refers sick American tourists to him. Dr. Reeves is also a CIA operative who enlisted after 9/11 to fight terrorism. After two years as an employee of the U.S. Intelligenge Service, he is disenchanted and wants out. Dr. Reeves is appalled by the brutal handling of terrorist suspects. It is his job to treat them and keep them alive long enough to obtain information or a confession.

Dr. Reeves loves Mexico, painting, and living day to day. He hates arrogance, disease, and human misery. His boss, Alex Law, is the chief of the CIA station in Mexico. He and his pal, Butch Nickels, have been in the spy business a very long time. Law is an alcoholic. His wife finds a lump in her breast that proves to be malignant. Dr. Reeves and his father (a surgeon practicing in San Francisco) arrange treatment for the woman in California where she undergoes a double masectomy.

Law has some clues that a group of al Qaeda in Mexico are plannning an attack. He worries they intend to bomb a city in California. Law's intuition is pretty good. A husband (Mohammad) and wife (Fatima) from Baghdad are set on revenge. Their young son was killed by an American bomb in Iraq. The husband, a physician, was mutilated by the same bomb. Unaware of her true background and her mission of destruction, Dr. Reeves falls in love with the beautiful woman who calls herself Dolores Rios. At one point, he kills a policeman and wounds another to rescue the woman. When her husband is bitten by scorpions, Dr. Reeves saves his life.

Members of the al Qaeda cell eventually capture Dr. Reeves and some of his friends. They plan to crash a stolen airplane into a California city. Dolores has a change of heart, but her husband is intent on revenge and becoming a martyr. Dr. Reeves offers to accompany the terrorists in exchange for Dolores being left behind. Still recovering from the effects of the scorpion bites, Mohammad figures it might be wise to have some medical expertise readily available. Shortly after take-off, Dr. Reeves manages to crash the plane but he is killed by gunfire in the process. The terrorist attack is averted. When Alex Law locates Dolores, he allows her to go free and start a new life. The doctor would have wanted it that way and Law allows him that much.