Known to a very few, highly placed individuals in the US government as Sapphire, Linda Blaine is a senior undercover intelligence agent. Though she is known to hostile governments-as well as some US allies-by several different aliases, her real name is not associated with Sapphire's more extraordinary exploits.

Linda Blaine/Sapphire/Sophia Lermontov-one and the same person-faced down the Soviet Politburo at the time of the Cuban Missile Crisis. But late in the Cold War, the Soviets bring in a new leadership in an attempt to change the balance of terror. At great personal risk, Linda/Sapphire must once again contend with officials at the highest level of the Soviet government to defeat them in their attempt to create a crisis. Their aim is to destroy American security and wreck the US as a major state, possibly leading to a third world war, which would involve the active use of nuclear weapons. Sapphire again brings her legendary courage and resourcefulness to her continued defense of America.