What Is and What Should Never Be

While on the trail of a Djinn, Dean wakes up one night and finds that he is in an alternate reality where Mary never died and John Winchester and his sons never hunted monsters. In this life, Sam is in law school and engaged to Jessica, and Dean has a steady job and a beautiful girlfriend. However, when a strange woman begins following him around , Dean realizes that all of the people that he and Sam saved have died, and has to decide if he wants to stay in his new life or return to reality.