In the finale of the Serum Trilogy, returning characters enter the scene to help save the day as a danger more sinister than they could have imagined threatens their world. John and Kellie have been growing closer in the last couple of months. Kellie's father, Mark, has been getting reacquainted with his family that he had been torn from 17 years ago. While working from home to appease his apprehensive wife, and with John's...