Supernatural kicked off its landmark 15th season by paying homage to the show's roots and bringing back some familiar monsters from season 1. First airing in 2005, Supernatural will have enjoyed a mammoth 15-year run by the time its final chapter comes to an end, representing a hugely impressive milestone for a series of its kind. Never ones to miss an opportunity to celebrate their history, Supernatural season 15 is bound to feature a string of cameos, callbacks and dramatic returns, with the likes of Kevin Tran, Amara and Eileen Leahy already set to feature in the final run.
Picking up right where season 14 left off, Supernatural season 15 finds Sam, Dean and Castiel fighting back against 3 billion souls currently pouring out of Hell after God opened the doors to the underworld. While the mass haunting is contained to Kansas for now, it won't be long until the dead take control of the entire planet, leaving Sam and Dean to figure out a way of closing the rift and stopping yet another apocalypse. Of course, cracking open Hell allows Supernatural to bring back a few popular villains from the show's long, illustrious history, and some of these were teased previously in season 14's final moments.
"Back and to the Future" brings back Constance Welch, otherwise known as the Woman in White, and Mary Worthington, generally referred to as Bloody Mary. Both of these characters featured in Supernatural's very first season, with Mary appearing in the appropriately titled "Bloody Mary" and the Woman in White being the Winchester brothers' debut case in the pilot episode. The season 15 premiere also brings back the spirit of John Wayne Gacy, who made his Supernatural bow only last season. Lastly, the ghost of Lizzy Borden is finally introduced - a famous specter that has been mentioned on the series, but never actually seen.
Having contained the ghosts for now, Sam, Dean and Castiel now must send their old enemies back to Hell and seal up the rift before more souls come through, and this means that both Mary and Constance, as well as their ghostly new pals, could play a further part in Supernatural season 15. It also seems highly likely that more past foes will come back to haunt the Winchesters before the credits roll on Supernatural's final episode.
One of the most frequent criticisms aimed at modern Supernatural is that the focus nowadays rests more with archangels, Lucifer and gods than the traditional ghosts, werewolves and vampires. As such, throwing back to Bloody Mary and the Woman in White was both a pleasing nod to the show's past and a neat way of reverting back to the traditional Supernatural format for season 15's opener.
Eventually, however, the big questions will need to be answered. God has been manipulating the Winchesters for a long time and is willing to risk the apocalypse just to teach them a lesson. That's not something Sam and Dean are going to let slide and with so much at stake, the brothers won't be able to jostle with ghosts and make pretty salt patterns indefinitely, especially with news that the door to the Cage has also been swung open.
Supernatural season 15 continues with "Raising Hell" October 17th on The CW.