While reading to his students, physicist and chemist Dr. Peter Wehller receives the news that his wife has been killed in a car accident. The police closed the case, but for Peter there were a lot of inconsistencies in this accidental death! Why was his wife sitting in the passenger seat when there was no one else in the car? And why did she have a puncture mark on the side of her neck? To find out what had happened in the accident, he dug out the "researching the past" project from his ideas drawer. But the journey into the past brought a surprise. The perpetrator himself came from the future.

Can Peter stop the murderer to save his wife without changing the history of time? Or has it already been changed by the murderer?