Supernatural’ season 9 summons its fourth episode of the year in “Slumber Party,” as Charlie's (Felicia Day) return becomes complicated when the boys stumble into a decades-old mystery of the true 'Wizard of Oz' within the Men of Letters base.

Last week’s ‘Supernatural’ episode, “I'm No Angel,” saw Castiel struggle to adapt to the challenges of humanity while on the run from the angels, and Dean was forced to make a difficult choice in the pursuit of his fallen friend, so what does the fourth season 9 episode bring?  What strange and unexpected challenges will the Winchesters face in the coming year?

Read on for your in-depth recap of everything you need to know about ‘Supernatural’ season 9 episode 4, “Slumber Party”!

In 1935, two men named Haggerty and Jenkins enter the Men of Letters base, quickly finding themselves bored with the uneventful Men of Letters lifestyle over the next few months. At long last, a famed girl named “Dorothy” (Tiio Horn) arrives looking for help to kill a witch, while back in the present, Sam presses Crowley to deliver the names of more demons. Dean brings back a ‘Game of Thrones’ DVD for a slumber party of sorts, while Sam next busies himself with rigging the ancient Men of Letters computer to help track angels.

After knocking over a mysterious bottle in the process of trying to fix the computer, Dean brings back Charlie for her expertise in decoding the ancient machine. Charlie reveals that she has experimented with hunting on her own, but finds the experience less magical and filled with the fantasy she’d prefer. While the group watches ‘Game of Thrones’ and awaits the files to transfer to Charlie’s computer, Dean notes how Sam has yet to come to consider the base a home, and the mysterious bottle downstairs uncorks itself and begins forming something on the wall behind it.

Back in the past, Dorothy presents a captive Wicked Witch that she’s been unable to kill, though the witch soon breaks free and possesses Jenkins, forcing Haggerty to kill him, while Dorothy flees to create a spell against the witch. Meanwhile in the present, the trio returns downstairs to find the bottle created a hole in the wall, out from which tumbles Dorothy. Once Dorothy acclimates to her present situation, revealing herself to indeed be the Dorothy from the 'Wizard of Oz' books, the time-traveler explains how she trapped the witch in the bottle with her for years, though both have now clearly escaped.

Dorothy explains that the witch has been seeking something within the Men of Letters base, for which Sam and Dean leave to find the wicked woman. While Charlie fan-girls, Dorothy admits her father, L. Frank Baum, got the mythology all wrong in writing his books, though Charlie reasons she could at least rig up some poppy field bullets that would stun the witch. Upstairs, Sam and Dean find that the witch visited with Crowley, revealing that she intends to find a key hidden somewhere within the base.

Sam and Dean find Charlie and Dorothy in the kitchen, while Dorothy explains that the key would open the portal to Oz (here part of the Fairy realm), returning the witch to her armies. Dean remembers that he found the key during an earlier inventory of the base, and kept it in his room. Sam and Dorothy explore the base looking for the witch, while Charlie and Dean search his bedroom. Dean finds the key, though the witch appears and lobs a blast at Dean that Charlie jumps in front of.

Dean finds the blast to have killed Charlie, though when Sam enters the room, Dean quickly urges Ezekiel to take over and return Charlie to life. Ezekiel warns that fighting the witch would prove a better use of his power than reviving the girl, though he ultimately acquiesces and brings Charlie back to life. Sam regains consciousness, swearing he heard Dean call him “Zeke,” while Dorothy reveals to Charlie that she actually died, rather than lose consciousness as Dean had told her. Sam and Dean continue to search the base, Dean taking the opportunity to remind Sam he should consider the base a home.

Dorothy explains to Charlie how her father created the stories as a revisionist history of sorts, though Charlie quickly points out that they seem to provide clues for Dorothy, giving the latter an idea. Meanwhile, the witch gets the drop on Sam and Dean, possessing them both as she sets about opening a portal to Oz. Charlie and Dorothy arrive to the Men of Letters garage, retrieving the two ruby slippers from Dorothy’s old motorcycle with intent to use the heels to kill the witch, before the possessed Sam and Dean appear. Both boys manage to overpower the girls, but Charlie manages to incapacitate Dean by kicking his ... Totos. We’ll say Totos.

Charlie finds the witch in the midst of her spell, stabbing with the shoes to finally kill the wicked woman and seal the portal before any flying monkeys get through. With the threat abated and the key in possession, Dorothy opts to return to Oz, inviting Charlie along with her for the adventure. Charlie accepts and says her goodbyes, promising to keep Dean’s secret about resurrecting her, and the boys watch the two head off down the yellow brick road.

OUR REVIEW:

Episodes like "Slumber Party" remind us that, for all its years, 'Supernatural' has always been an oddball road show with a cast of two at its core, rarely settling into familiar settings and character dynamics longer than a season or two. A bottle episode within the Men of Letters base, even one that teases the world of Oz lying just behind its doors, certainly feels like an odd fit for the show, which itself hasn't had much of a centralized plot to bottle away from since the fifth season.

Even so, a 'Supernatural' flight of fancy that brings to life its own take on the 'Wizard of Oz' mythology with Felicia Day at its core to crack wise tonally feels much more in keeping with the later seasons of the series, even if the execution occasionally stumbles. You see, part of the comfort behind keeping the brothers on the road lies in the fact that we'll have danger at every turn to distract from the character relations percolating under each scene, a familiar formula that feels a bit claustrophobic when the boys have less organic reasons to break with the action. Ergo, give the boys a mission, and they'll find time to discuss their feelings during an episode-ending drive, have Dean interrupt a literal witch hunt to discuss Sam's feelings on the Men of Letters base, and the beat becomes much more contrived.

Of course, that isn't to suggest that "Slumber Party" does away with the main narrative threads altogether, as we still have Ezekiel popping in to deliver some gruff exposition on Sam's health, Crowley contributing to the witch hunt, and a minor break in Dean's secrecy over Castiel and the blackouts, but Felicia Day fun prevailed as the theme for the hour. And of course, Felicia Day provided her requisite charm and levity against the backdrop of 'Supernatural' forces, ending up in an expected trip to Oz that thankfully kept any Dorothy-Charlie shipping to the subtext. We love the character mind you, but less so when the writing denigrates Charlie's sexual orientation to a punchline in almost every appearance.

All in all, "Slumber Party" offered up some good fun for its hour, Felicia Day and the intriguing Oz reinvention putting in most of the work to keep things fresh, though we weren't without a few hiccups. The wicked witch wasn't given much of any consideration as a character for one, while Sam and Dean's weekly bonding test seemed a bit contrived without external forces to keep the plot moving. Next week looks even sillier by comparison, but who can resist Jensen Ackles barking at a mailman?

Well, what say you? Did you get your fill of scary ‘Supernatural’ action? What did you think about “Slumber Party”? Give us your thoughts in the comments, and join us again next week for an all-new recap of ‘Supernatural’ season 9 episode 5, “Dog Dean Afternoon,” on The CW!

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