**From the Oscar-nominated screenwriter of Arrival comes a phenomenal speculative thriller about a federal agent and a therapist who team up to stop an otherworldly killer. **Federal agent Grant Lukather works for an unknown department of Homeland Security called Predictive Analytics. They look for patterns in tips and chatter to prevent a terrorist event before it happens. One of these calls, about a possible explosion in New Mexico, leads Grant to a case with unimaginable consequences. He meets Sarah Newcomb, a therapist who uses past-life hypnosis in her treatment but has recently stumbled upon a phenomenon that seems to defy logic. Grant follows this thread to another a copycat killer case in Colorado. With the help of one of Sarah’s patients, they embark upon an investigation that spans multiple states, timelines, and consciousnesses. With limited time and only a tenuous grasp of how this phenomenon works, the unlikely trio are in a race for their lives—past, present, and future. Full of thrilling reveals, stunning plot twists, and a mordant sense of humor, Simultaneous is a mind-bending, one-of-a-kind thriller by a true genre star.