The fourth season of the American television medical drama Grey’s Anatomy, commenced airing in the United States on September 27, 2007 and concluded on May 22, 2008. The season continues…

When hunters gather together to celebrate the life and tragic death of one of their own, Sam, Dean, and Mary must take action when a demon starts picking off hunters…

A plan to contact the Ark is put in motion after Raven crash lands on Earth. Meanwhile, Abby exposes Kane’s plan to reduce the population of the Ark.