Supernatural Season 9 continues tonight with a “Slumber Party." Here's a look at new photos and preview videos from the upcoming episode:

Season 9 Synopsis: "The thrilling and terrifying journey of the Winchester brothers continues as SUPERNATURAL enters its ninth season. Sam (Jared Padalecki) and Dean (Jensen Ackles) have spent their lives on the road, battling every kind of supernatural threat. Over the years, after dozens of bloody adventures, they have faced everything from the yellow-eyed demon that killed their mother to vampires, ghosts, shapeshifters, Angels and fallen gods. They even came face to face with Lucifer and the Four Horsemen in averting the Apocalypse. With the help of allies — both human and supernatural — they’ve discovered that every threat they vanquish opens a new door for evil to enter in. In the show’s eighth season, their supernatural hunting expedition led them directly into an age-old power struggle involving the King of Hell, legions of warrior Angels and a series of divine trials to prove themselves worthy of sealing the Gates of Hell forever. With the help of their protector, the fallen angel Castiel (Misha Collins), Sam and Dean’s lifelong quest to rid the world of evil will take everything they’ve got. As dawn arrives after their endless struggle and sacrifice to defeat the world’s monsters, they know that, come nightfall, something otherworldly — something supernatural — will claw its way out of the shadows, demanding their attention."

Episode 9.04 Synopsis: "Sam (Jared Padalecki) and Dean (Jensen Ackles) discover that the table in the Men of Letters house (the one that lit up like a Christmas Tree when the angels fell), has an ancient computer attached to it. They figure if they can get the computer on, they can track the angels. Who better to call for help than the best IT girl there is, Charlie (guest star Felicia Day)? While moving the massive computer, they dislodge a hidden hexbag that unleashes a magical green-webbed wall. Sam and Dean break through it and discover the one and only Dorothy (guest star Tiio Horn) from Oz. She had trapped herself and the wicked witch (guest star Maya Massar) in the web years ago to stop the witch from finding the key that would open the gate that connected their world with Oz. With the wall broken, a massive and magical fight ensues that threatens to destroy the Men of Letters house. Robert Singer directed the episode written by Robbie Thompson."