Chyna, a beautiful 26-year-old girl, can't get herself to sleep and looks out her window, talking to the moon. This is her very first night in her BFF's family's home. As it soon turns out, her insomnia is the only thing that saved her from a psycho - Edgler - who's found his way into the house and wants nothing more but to strangle every last person inside.
This maniac doesn't care about other people and has only one goal in life: to satisfy all of his sick desires as they come forward, to enjoy the riveting sensations and to live without remorse, second thoughts, fear, hesitation, or limits. Intensity is what he's after, and Chyna becomes a prisoner in his far-reaching hands.
However, she's not one of those sweet and innocent girls who can't take care of themselves: she's been through a lot, and that made her a survivor, a self-made fighter. At the same time, a lunatic murderer is not something she's used to dealing with, and this test proves to be a life-defining experience for her. Chyna concentrates on making it out of the house alive, but, when she discovers the identity of the maniac's next victim, she decides to play with fate and do everything in her power to save that poor soul.
The girl is in danger, and if Chyna fails to do the impossible - stop Edgler - she'll die. There's no room for error, and even the tiniest mistake can result in both Chyna's and the new victim's death. Can the young hustla beat the killer at his own game? Dean Koontz is known for writing the most gripping and suspenseful thrillers of our time, and Intensity is one of his best books to date.