Henry sets out to find the Gehenna Key, which will allow his master Moloch to escape from Purgatory with an army of the damned. Meanwhile, Ichabod tries to free himself from his buried tomb, and Jenny must escape the Hessians holding her on Henry's behalf.

Ichabod and Abbie concoct a daring plan to try to rescue Ichabod's wife from the Headless Horseman by resurrecting a Frankenstein-like monster created by Benjamin Franklin. Frank faces new trouble after revealing the true details of his encounter with a demon. Jenny finds herself at odds with the new sheriff in town.

After a bank robbery turns violent, Abbie and Ichabod embark on a hunt for a mysterious silver coin that has more power than meets the eye. Captain Frank Irving is put in the position where he must choose between his family and the greater good. The Mills' sisterly bond is put to the utmost test.

Abbie and Crane's search for a missing Sleepy Hollow child reveals a creature akin to the Pied Piper, whose legacy with the child's family extends back to a centuries-old curse.

Sheriff Corbin's son returns from war, but his strange behavior leads Abbie and Ichabod to question his intentions.