The Winchester are going to get an unexpected ally (PHOTO)

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 published the official plot synopsis of the second episode of Supernatural Season 15, titled “Raising Hell.” As the Winchesters continue to face evil souls released by God from Hell, they are being assisted by guest star David Haydn-Jones, who will take up his position as Arthur Ketch. Arthur Ketch was a member of the British Men of Letters who was murdered by the mom of Sam and Dean, Mary Winchester, and also revived by Rowena, first appearing in Season 12. Since then, while helping the Winchester Brothers from time to time, Ketch has been working as a mercenary. SUPERNATURAL “Raising…