Underground Guardians - Protector By Lisa Renee Jones

In their quest to create a stronger fighting force, the elite Black Knights unwittingly give birth to a dark force, led by a man of evil. Now the Knights must battle their counterparts to keep civilization out of harm's way. There is one man whose destiny it is to keep humanity safe, but Mason Alexander will need the help of his soulmate to accomplish his goal.

Forever changed by the medical experiments he underwent, Mason needs Holly Heart to teach him how to control his special talents. Holly, a doctor who has devoted her life to genetic research, is frightened by the changes she finds in Mason, yet she is spellbound by the desire she feels for him.

As Mason and Holly join forces to defeat the enemy, passion explodes, burning as hot as a raging fire. And as their souls unite, Mason fears that if Holly ever sees the beast within him she will run forever, dooming him to the dark side.