Now that the MillCranes know their demon's name, it's all too obvious how to defeat him: A 17th century French lantern! Much like the ones Benjamin Franklin acquired during a diplomatic mission to France during the Revolutionary War! Of course! And hey, as luck would have it, Jenny knows just the place to find such a magical lamp. It's a good thing the show has already established that Jenny used to do business with the local relic shoppe; otherwise, this lightning-fast turnaround would be a little too ridiculous, even by Sleepy Hollow standards.
Jenny directs Abbie and Ichabod to a huge Doomsday Prepper compound, where the lantern lies among a crowd of treasures that may come in handy as the end of the world draws nigh. Though nabbing it would seem to be a job for criminal extraordinaire Jenny, law-loving Abbie actually volunteers to steal the object; ain't sisterly love grand? And then the Clue Crew gets a disturbing phone call: Captain Irving says that he's running out of time, and he's heading to the archives so that he can deliver the bible to Ancitif.
From this, the gang deduces that the unthinkable must have happened -- the demon has possessed the Captain's little girl. And sure enough, Ancitif has made the leap from Detective Jones (now the late Detective Jones -- we hardly knew ye, Devon!) to Detective Morales to its trump card, Macey Irving herself. Now that he's within this last vessel, he's having a grand old time going full-on Regan McNeil, even murdering Irving's poor priest in a way that recalls one of The Exorcist's most famous scenes. (Warning: Really, really not for the faint of heart. Aaaaaand now I'll never sleep again. The things I do for you people.)
Back to The Compound, where Ichabod and Abbie find the lantern faster than you can say "ancient Aramaic, obviously." It's nestled among what look to be several goblets. Like, a lot of goblets. They hit a minor snag when they exit the lantern's hiding place, only to find Uncle Jack's army fully embracing its right to bear arms. Thankfully, Jenny appears in the nick of time, upholding her own Second Amendment rights -- which causes the Preppers to respectfully retreat. I've said it before and I'll say it again: We need a Jenny prequel, stat.
NEXT: But first, we need to extract a certain demonic visitor