With the Headless Horsesman (Richard Cetrone) trapped and contained in an underground Masonic cell designed by Thomas Jefferson, Captain Irving (Orlando Jones) reaches out to the recently-released psychiatric patient Jenny Mills (Lyndie Greenwood) to help with the Hessians working to free the Horseman while Abbie (Nicole Beharie) and Ichabod Crane (Tom Mison) try and convince Andy Brooks (John Cho) to help them communicate with their prisoner.
Although Jenny and Irving are able capture the Hessians they can’t stop the group of blowing up Sleepy Hollow’s power plant which turns the entire city dark – including the UV lights helping to keep the Horseman contained. The group are further outsmarted by Moloch as the demon uses its control over Brooks to call forth a legion of demons and free the Horseman.
Flashbacks from this week’s episode involve Katrina (Katia Winter) and her relationship with Ichabod’s best-friend Abraham which are brought to light by the Horseman’s head-stump coughing up Katrina’s necklace. With Brooks speaking for the Horseman, Crane learns how his connection to Abraham is connected to the Hessians who used his betrayed and angered friend’s dying body as a vessel for one of the Four Horseman of the Apocalypse.
“Necromancer” adds quite a bit of information to ongoing storylines as Jenny begins helping Abbie and Ichabod’s quest, the reason for Katrina being stuck in limbo is revealed, and we learn just what Brooks’ connection to the Horseman truly is as well as the identity of the body whose form Death has been riding around in. The episode also reveals the fact that the Horseman, even though is blood tie to Crane has been severed, isn’t allowed to kill Ichabod Crane meaning Moloch must have specific plans for the soldier out of time.