Watch Supernatural season 7 episode 19 with an episode name of "Of Grave Importance" which aired April 20, 2012 Friday night on The CW. In the episode, the Winchester brothers, Sam and Dean got a call from a long time friend and a hunter named Annie Hawkins. She asked for help from the brother regarding a recent sightings involving ghost in a certain town. When the brothers decided to go to the said town and help her, she suddenly disappeared without trace and the hunt begins for Sam and Dean.
It seems that the culprit involve on the said disappearance is a powerful ghost from the haunted abandoned house in the said town and they must face it to find Annie. The question now is will be Bobby still there to assist them in this current battle against evil? How come the brothers can't see them and Bobby unable to allow himself to be seen to the brothers? Will he can be seen later or will she lives again through Castiel?
See a glimpse of Supernatural 7x19 - Of Grave Importance below.