Supernatural is an American horror television series that concerns the paranormal. The series, which is filmed in Vancouver, BC, Canada, debuted on September 13, 2005 on The WB, and is now part of The CW's lineup. The second season premiered on September 28, 2006, and the third on October 4, 2007, though its run was interrupted by the writers' strike. Supernatural returned for a fourth season on September 18, 2008.

Source: Wikipedia