Halloween spoilers below.
Call me Bertram Fetterer, 'cause I clocked it!

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Halloween spoilers below.
Call me Bertram Fetterer, 'cause I clocked it!
Time for Halloween predictions!
I don't normally make Halloween predictions, thanks to a combination of childhood-based aversion to predicting stories incorrectly and a fervent enjoyment of being surprised by stories; but I think I found actual clues this year, and the prediction built itself. I will once again disclaim that I have not looked at the Faire's website since last weekend, just in case they added anything to the scenario; so anything that is or isn't there now had no influence on this.
Furthermore, I will once again offer the following entreaty: while I'm not half so arrogant as to assume that my predictions are accurate, they very well might be. Therefore, if you like being surprised by the Halloween plot, please read no further. If you got chills at Morgan la Fey's echoing laugh and sat with mouth agape as she strode down the aisle; if you made the connection like a clap of lightening that these two new characters were Titania and Oberon and proceeded to physically bounce up and down in your seat in excitement; if you realized that Sir Walter was leading up to confessing to having been a ghost the whole season and then involuntarily leaped up upon hearing Zach's voice; if you turned to your friend twenty-six seconds before the introduction and exclaimed “this is fucking Merlin!”; and if you treasure those moments as I do, then return to this post after witnessing the new plot, just in case I'm right.
(The rest of this post is REALLY badly written, but I couldn't make the words go well.)
I formed this prediction all the way back during Opening Weekend. When the Celtic Revels performed at Finale, they started by bringing out the iron cage containing the fae masks, saying that they had found these masks in the woods and the masks would play no part in their performance. They set the cage to the side, did their number, accepted their accolades, retrieved the masks, and left the stage, Monty exclaiming “Let's go burn these!” Including the masks in this manner struck me as an odd choice, for it was wholly unnecessary; unless as a means to both introduce the concept of the masks to more people and to hint at something more to come with them.
The fae masks are not new to this year, but to last year. For any who do not attend the music shows, the Celtic Revels' perform their second set both this year and last year almost entirely whilst wearing masks that allow specific fae to posses or inhabit the characters. Last year, the fae in question seemed to have no real agenda, and might have been an in-universe gimmick of the troubadours and not fae at all (mostly). This year, however, the masks are involved in both sets, being established in the first and worn in the second; and within the world of the story, they are most certainly not a gimmick. Likewise, the fae that posses the characters – the Court of Revels – decidedly have an agenda this time. They speak of having been banished from this Realm, of their echoes lingering in the masks, of the stars aligning in such a way as to allow them to cross back into the mortal plane; of the abundant curiosity of humans, of luring these hapless mortals to their bower and compelling them to don the masks; of their intention to remain here – whether to posses these four humans permanently or just long enough to somehow manifest their own forms; they do not specify. The mortals spend the set locked in struggle with the fae, and manage to cast them from themselves near the end after an absurdly powerful original number about the Court of Revels. They're all quite disoriented and disturbed, and lock the masks in an iron cage for absolutely no reason whatsoever, they're not scared you're scared.
There is precedent from 2014 for a music group to become the Halloween antagonists: the Sirens were literal sirens that year, and caused some sort of trouble for Halloween. As stated, the fae masks for the Celtic Revels are not new to this year; but if ever there were a year to involve them for Halloween, it's this one, for one of the Revels is also a lead – one quite close to the ruler of Scotland / potential future ruler of England. Remember those options of the fae permanently possessing the Revels or possessing them long enough to manifest their own forms? There's a secret third option: possessing the Revels in order to get close enough to more useful targets of possession.
There are so many ways this concept could go, and I'm not running through any of them here. Instead, I'm going to relay some more instances of the Revels performing at Finale, and how the performances support this theory.
Week two's performance went much the same as week one's. The Celtic Revels brought the iron cage of masks onstage with them (although this time, they said that they brought the masks along because the masks oughtn't be left unattended), performed their number, collected the cage, and left.
I was absent Sunday of week three (Heroes), and know not whether the Revels performed or what form their performance might have taken. As far as I know/remember, they next performed at Finale week five (Wizarding). When they were announced, another Irish character (Rory) came forward saying that he could not find the Revels backstage but he found this empty cage. The fae-inhabited Revels then materialized from behind the throne and performed the absurdly powerful original number co-written by JR Rouse and Madison Caudullo about the members of the Court of Revels. As in the second set, the mortals cast out the fae at the end of the song, collapsing and waking as though from sleep, disoriented and disturbed, viscerally relieved to find the iron cage at hand.
When the Celtic Revels performed at Finale week six (Celtic), Rory once again came forward to say he could not find them backstage, but he did not get far in his speech before falling into some sort of trance and announcing the Court of Revels. The fae-inhabited Revels came onstage, performed Follow Me Up To Carlow, and then left the stage still possessed.
Now, this clear progression did not continue, for the Celtic Revels performed totally normally weeks seven and eight (Oktoberfest and Time), but it still gave me confidence in my prediction. So confident was I, in fact, that for the final main-season weekend, I elected to entirely forgo Music with Her Majesty – you know, the show that I knew for a fact will be different for Halloween – in order to watch the Court of Revels set both days, for I believe that one will change, too. Not by much: probably just the mortals not managing to cast the fae out and the fae immediately going to Globe after the set in order to play whatever role they will in the final third of Music with Her Majesty.
Another point in favor of this theory is the prominent presence of all four Revels in the chessmatch: two providing accompaniment, one fighting on the board, and one doing both. This would be a very convenient means of having them in prominent positions for Halloween whilst fae-inhabited without total fundamental alteration of the show.
(Honorable mention goes to the substantial bout of wishful thinking I had back before the season began of the Halloween character being played by Dan Schindlar, whose presence and performance I miss dearly, ideally as the ghost of Don Gibbs.)