Books in the Defend and Protect series

After four US Secret Service Special Agents die in unusual circumstances within a ten-week span, FBI Special Agent Faith Malone is put in charge of the investigation. She'll have to work alongside USSS Agent Luke Powell to bring a killer to justice--before his name joins his friends' on the list.

Driven by a traumatic event in her past, Dr. Ivy Collins is on the precipice of a scientific breakthrough after years of research and sleepless nights when dangerous circumstances demand that she give it all up--to save someone else. Can US Secret Service Agent Gil Dixon work with her to help save her work--and her life?