A group among Cuban military forces is conspiring to overthrow Cuba's communist government. They have prepared a rebellion, but the unexpected arrival of Russian troops in the island prompts the conspirators to seek military backing from the United States to avoid a civil war. The leaders of the conspiracy call on the Vatican to be the liaison for the secret contacts between them and the U.S. Government.

The agreed participation of American military forces complicates when the U.S. intelligence agencies discover a plan, designed by Fidel Castro, to blow up a nuclear reactor operating in the island. Castro's intent is to cause a huge radioactive fallout over the United States territory if an invasion by American troops ever occurs.

The novel is a tribute to friendship, love, and patriotism, and a reflection on "the man and his circumstances."