The CW has announced that it is working on a spin-off of Supernatural. The long-running series - entering its ninth season on October 8th - will have a "planted" or "backdoor" pilot during the upcoming season. This is similar to what The Vampire Diaries did last season with The Originals: one episode will introduce new characters that could potentially see a new series for the 2014-2015 season. The episode, to be written by Supernatural supervising producer Andrew Dabb, will "explore the clashing hunter and monster cultures of Chicago."
Could this signal the end of Supernatural? The series is not only the CW's longest-running show, but one of the longest-running scripted shows currently on television. But I think there is Supernatural fatigue. The storylines are starting to feel repetitive and uninspired, and I have to imagine series stars Jared Padalecki and Jensen Ackles are getting bored. A spin-off would be a good way to bring Supernatural to a close while keeping the staff employed and the fans satiated.
Source: Deadline