Mind Games - Harp Security, #4

The daughter of a schizophrenic, Dr. Jane Evans prioritizes order, control, and-above all-her work in a psychiatric research lab. When an attempted kidnapping threatens to derail the project she's on, her boss hires a bodyguard. He's everything Jane is not, and if she can survive, she may even learn to like the difference. Eric Sorensen owes Jane a debt he can't possibly repay. Without her tutoring, he would not have made it through college, would not have the life he does.
But none of his memories of college Jane prepare him for adult Jane. When she suddenly disappears, he follows her trail to a secret lab in a cartel-controlled Mexican jungle. Rescue seems impossible but Eric's not the type to give up, even if it means trading his own life for hers.