The final season of Supernatural is coming next month, and a newly released episode synopsis hints that the Winchester Brothers and Castiel will receive support from a surprising source.

The CW has released the official plot synopsis of Supernatural Season 15's second episode, titled "Raising Hell." As the Winchesters continue to face evil souls released from Hell by God, they receive assistance from guest star David Haydn-Jones, who will reprise his role as Arthur Ketch.

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First appearing in Season 12, Arthur Ketch was a member of the British Men of Letters who was killed by Sam and Dean's mother, Mary Winchester, and also resurrected by Rowena. Since then, Ketch has worked as a mercenary while assisting the Winchester Brothers from time to time.

SUPERNATURAL

“Raising Hell” – (8:00-9:00 p.m. ET) (TV-14, DLV) (HDTV)

SENDING OUT AN SOS – Sam (Jared Padalecki), Dean (Jensen Ackles) and Castiel (Misha Collins) call on Rowena (Guest Star Ruth Connell) to help keep the evil souls at bay and get an unexpected assist from Ketch (Guest Star David Haydn-Jones). Robert Singer directed the episode written by Brad Buckner & Eugenie Ross-Leming (#1503). Original airdate 10/17/2019.

Season 14 ended with the Winchesters failing to kill God, with the deity unleashing the souls of Hell on Earth to bring about the apocalypse in retribution for Sam and Dean's defiance. However, with Ketch back in the fold, perhaps it will be enough to save the day.

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Returning Thursday, Oct. 10 at 8 p.m. ET/PT on The CW for its final season, Supernatural stars Jensen Ackles, Jared Padalecki, Misha Collins, and Alexander Calvert.