Complete story — includes the ending
After Ichabod fails to show up for a meeting with Diana, Jenny searches his apartment and finds traces of spider silk, which Jake identifies as belonging to the "Sicarius Spei", a demon identified by Benjamin Franklin in 1778, and capable of trapping its victims in an illusion of their greatest fears until they are driven to absolute despair. Ichabod finds himself on trial for the "murder" of Abigail Mills, with Henry acting as prosecutor. While searching for the demon's cave, Jenny is arrested for trespassing; Diana bails her out and the two find Crane wrapped in a cocoon. Unable to free him, they return to the Vault and conduct further research, learning from an account left by Grace Dixon that the same demon was responsible for the suffering Washington's forces endured at Valley Forge. Dixon also describes a flammable compound she invented to destroy the demon's webbing, and Jake and Alex go to retrieve torches, during which they witness Dreyfuss' bodyguard Jobe steal a map of ley lines. The demon shows Ichabod a vision of Molly and the others dying because of him, and while Jenny manages to kill the demon, he attempts suicide. Diana has Molly indirectly speak to Ichabod, freeing him from the illusion. Alex and Jake take a sample of the demon's webbing back to the Vault, where it forms an image of Henry's face.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, Sleepy Hollow season 4. HTML formatting and reference markers removed. · Content license