Two Graves by Douglas Preston & Lee Child

This is the third and final installment in the “Helen” trilogy which answers a few questions but raises a lot more about the intriguing main character, special agent Pendergast.

For years, FBI special agent Pendergast had believed that his wife, Helen, was dead, killed by a lion in Africa. After he found evidence that she had been murdered, his investigation into who might have killer her, raised tantalizing suggestions that she might actually be alive.

Pendergast’s quest for the truth takes him on a suicide mission to Brazil where he discovers that horrific Nazi medical experiments, especially on twins, have continued. He also learns that his beloved wife had been a victim of these atrocities, and that Helen and her twin sister are both now dead. There’s more to discover here, but I don’t want to give anything away.

Meanwhile, his ward Constance Green, who had been committed to an asylum for the criminally insane for killing her child has found a friend in the doctor who had her put away. That doctor, Dr. Felder risks his life to help her prove her sanity.

This is another gripping installment in the FBI special agent Pendergast series. There are complicated plots, interesting characters, lots of action, and these are extremely hard to put down.