Rylee Cooper has been 18 for the past 63 years. Now, something you need to understand: this isn't considered abnormal in her reality. In fact, it's extremely common. This society was born with the ability to maintain their youth. However, the aging process continues after they've found their significant other. That way they can grow old together. Sure, it sounds like a fairytale; a dream come true. But when you've been sitting around in the same body for so many years, being eternally eighteen doesn't sound so enticing. Others are obsessed with the idea of being immortal. One person in particular is a killer. He's been murdering his soul mates over the years in order to maintain his youth. After taking a liking to Rylee, he plans on ending her life. Lyle Walker is Rylee's best friend, who has completely devoted his heart and love to her. Lyle is determined to keep Rylee safe from harm, but when the killer shows up for a fight, that task is deemed harder than he originally planned.