Sadly, Meg gets stabbed to death by Crowley in the season 8 Supernatural episode "Goodbye Stranger" after helping Sam, Dean, and Cass thwart Crowley's latest evil plan. Unfortunately, the real-life reason for Meg's departure from the show was Miner's struggles with multiple sclerosis.

Before dying, John tells Dean, if he can't save Sam, he'll have to kill him, should he become evil. The fourth season episode "On the Head of a Pin" reveals that the demon Alastair tortured John in Hell for over a century, with John refusing the demon's offer to stop if he himself would torture someone else.