Sleepy Hollow takes a turn away from the Headless Horseman in "Blood Moon," about a witch risen from the grave to take back the ashes of the ancestors of those that burned her on a pyre. As Irving comments in this episode, he's trusting in Abbie and Ichabod to do the dirty work because he really doesn't understand what's going on, and he doesn't care to. He's packing up and heading to Albany, which explains his lack of screentime in this episode.
Ichabod's still trying to learn what everything does in the 21st century, but Abbie nicely labels everything for him, including explaining that if he presses a red button, coffee will come out. For the most part, Ichabod takes everything in stride; if I was thrown into the future, I think I'd be freaking out a little more. But he's got work to do: his wife Katrina comes to him in a dream and warns that a witch will rise during the blood moon to take back her ashes.
In fact, she does, with a little help from Andy Dunn (who was killed and brought back to life by the big demon guy, so he has a crinkled neck). It's clear that the demon's intention is to raise all of the evil dead witches to try to bring about the Four Horsemen of the Apocalypse. How all of this relates, how they use a medallion to raise the dead, isn't clear yet, but Sleepy Hollow has its own mythology that it's using and it hasn't allowed the audience knowledge of it yet.
"Blood Moon" isn't as good as the pilot, if only because its lore gets a little cheesy after a while. Even though Ichabod has been transported 250 years into the future, he seems to have a good sense of direction, because he realizes that there's a series of tunnels underneath the town that house the bones of witches. He also knows an awful lot about witchcraft, even though he was only a historian and a soldier. It's not really believable, and "Blood Moon"'s focus on exposition to tell the story of Serilda the witch feels sloppy.
There's also a cringe-worthy moment where Abbie gives us a flashback story when she was picked up for stealing drugs from a drug store. The arresting officer was none other than her partner Corbin, who takes her to a diner, sits her down, and tells her to choose between doing good or evil within five minutes. So she chooses good, obviously, although something about this story doesn't really ring true - a teenage junkie is going to take Corbin seriously after knowing him for ten minutes? Farfetched at best, and it shows that Sleepy Hollow's not really sure what to do with Abbie's character yet.
Everything is just a bit too convenient in "Blood Moon," from the pair figuring out exactly what's going to happen thanks to an ancient book to them showing up just in the nick of time to blow up Serilda without a hitch. Sleepy Hollow is going to go the procedural route for a little while, which is alright to me, but it's got to be a little bit more careful with how it explains where these witches come from. Ichabod can't be the brain of the group all the time - if he is, it quickly destroys whatever cover he has created, and he'll stop being a mystery. Instead, he acts as the deus ex machina, and that's not going to cut it in later episodes.