How do you defeat an enemy that's inside your head?
Heath Kavanaugh lost years of his life working for a covert agency that ended up being the enemy. Knowing they put something inside his head—constant, incomprehensible whispers—is driving him crazy.
He needs answers, but they’re nowhere to be found.
What he definitely doesn't need is to fall hard for his Linear teammate's younger sister, Jacquelyn—the adorable linguistics doctoral student who happens to be in the wrong place at the wrong time.
Especially when Heath’s attention puts her directly in the path of a danger he thought was gone for good. To stop it, they’ll have to figure out what’s in his head. And hope it doesn’t destroy them all.
"Another GREAT book from one of my favorite series – thrilling, funny, smoking hot!" ★★★★★ - Tanja Goodreads Review
★★★★★ "A top must-click author... Definitely would give more stars if I could!" ~ Sophie R Reviews Goodreads
"This is such a fantastic series. It just keeps getting better and better." ★★★★★ - Country Girl Reviews
"The first thing that I loved about this book was that the female wasn’t the perfect leggy blonde. The Linear Tactical series is full of the alpha males and kick as females at their sides. To me, that is the perfect romantic suspense." ★★★★★ Lisa S Reviews Goodreads
★★★★★ "heart-pounding suspense and amazing chemistry" - Sandra Goodreads Review
"A blockbuster of a book!" ★★★★★ - Mary Goodreads Review
★★★★★ "Oh YES! Shadow is exciting, hot and keeps you guessing. The chemistry between Heath & Lyn is everything you want in romance. Absolutely Couldn't. Be. Put. Down." - Hot RS Reviews