After her husband's death, Catherine Brooks is ready to go back to work—almost. She volunteers at a shelter for homeless teens, Lost Angel, thinking it will ease her return to the classroom. There's nothing easy about irascible shelter manager Luke Starns, though. His cool detachment rubs her the wrong way, especially when he warns her not to get too attached. Still, the soft heart she senses beneath his stern exterior keeps her coming back—and his face pervades her thoughts.

It's not that Luke finds Catherine's easy charm and free spirit unappealing—quite the opposite. Life on the streets is hard, and discipline is the only ladder that'll get and keep these kids out of trouble. He knows what it's like to care too much, only to have the rug yanked away. He tells himself he's simply trying to save her the same heartache.

Yet Catherine has him rethinking his approach to life. Just as he lets his guard down, though, a murderer begins stalking the mean streets near the shelter, putting everything they care about at risk. Including their lives.