- "Who's the true master of lighting now, Benjamin?"
- —Japheth Leeds
Japheth Leeds was an inventor and an acquaintance of Ichabod Crane's and a rival of Benjamin Franklin. Eventually, as his experiments grew more bizarre, and his appearance twisted because of them, he became known as The Jersey Devil.
When the name Jersey Devil first appeared, Crane checked the references to the Jersey Devil dating back to 1777. It was discovered that there were a dozen unexplained deaths in New Jersey in the last ten months, and the last were two joggers in Atlantic County Park. Crane checked his maps, and told Abbie that he met Benjamin's rival, Japheth Leeds there once.
A flashback then shows Crane writing in the woods when Leeds approaches and asks if he intends to be another of Franklin's whipping boys. Leeds insists that Franklin is no rival, because of his lack of skill, and tells Crane to pass on his message. Crane wonders why Leeds' Electrostatic Inducer is superior to Franklin's lightning, and Leeds merely tells him that he chose the wrong mentor. Leeds' also work includes isolating animal traits and using them to augment humanity: genetic manipulation. Leeds experimentes on himself, altering his body. Leeds drinks his own formula and mutates into the creature that will be known as the Jersey Devil.
Crane finds Franklin's comments about Leeds in his Almanac, and finds a coded message. Franklin says that Leeds had turned to alchemy and ancient magic, turning his back on the scientific community. Crane and Abbie realize that Leeds is still alive over 200 years later, and head to Atlantic County Park.
At the park, Crane and Abbie find the ruins of Leeds' cabin and in an old stove marked with alchemical markings. Crane finds a hidden switch, and the entire platform moves aside to reveal a passage downward. They descend, and the gaslights activate automatically, revealing Leeds' lab. The Witnesses find notes with references to the Hidden One. Crane realizes that Leeds is a worshiper of the Hidden One, and came in service to his master. Abbie finds a necklace in the shape of the temple symbol. Crane doesn't know what it means but suggests that it represents evil if Leeds had it.
Crane finds Leeds' research and notices that Abbie is staring single-mindedly at the symbol. She has also found a wax cylinder from a phonograph, and Crane plays it on Leeds' device. It is a movie projector, and Leeds has recorded information on the Hidden One. He documents how the gods of the ancient era ruled over humanity, and Pandora was one of the servants. The Hidden One is outcast and condemned to live in the Catacombs, and Pandora brings the offering to him. She once offered him a flower to bring him a bit of joy, and the Hidden One eventually tells her that he stands guard over all of the evil in the world, hidden in a Box. He summons the Box and shows it to Pandora, and explains that the evil within the Box is filtered through his brother's golden hourglass... and the evil is the only thing that can destroy his brother. Pandora and her allies unleash the Box's contents, however, humanity betray the Hidden One and locks him away.
Crane realizes that the gold of the stolen artifacts is the key, and Abbie figures that Leeds plans to recreate the Golden Hourglass. The two relics are pieces of it, and the Hidden One plans to use the power of the monsters he summons using the Hourglass. The transformed Leeds enters and recognizes Crane. Crane says that Franklin knew Leeds' true nature, that he was an abomination.
The Jersey Devil pours himself a drink, and insists that his god is bent on restoring power to the worthy. He describes a golden age where genius is recognized. He then lashes out at Abbie, and the Witnesses open fire on him. He's immune to their bullets, but Crane manages to stab him in the back with his own scorpion tail, but scratches himself on the stinger. Leeds recovers and knocks Abbie unconscious. Crane collapses from the venom and Leeds picks up a technology-laden staff and walks out.
Abbie comes to and has the dying Crane tell her what she needs to make an antidote. She does so just in time, but she freezes as she sees the symbol again. Crane whispers her name, snapping her out of thrall. Abbie finishes her job and gives him the antidote. As she waits for him to recover, she grabs the symbol. Crane finally comes to and Abbie apologizes for being distracted. He realizes that the symbol captured her attention, and warns that it is likely evil, but Abbie says that she's needed it for months. She saw it on the temple wall and it gave her peace, and still does. Crane says that soldiers returning from the war do what they need to carry on.
Crane mixes an explosive to blast open the door. Jenny calls and reads Abbie a legend about an hourglass artifact that bestows omnipotence on the user. The key ingredient is the Fire of the Gods, which will transform the relics into the Sands of Life. Abbie tells Crane what Jenny has discovered, and he realizes that the staff the Devil took is his Electrostatic Inducer. They assume he is going to the highest point in the area.
Leeds begins the ritual. He places the Inducer in the bowl just as Crane and Abbie arrive. Crane warns that the Hidden One cannot be trusted, and Leeds says that he chooses him as his master. He activates the Inducer and lightning strikes it, melting down the stolen relics, transforming into the Sands of Life. Abbie opens fire without effect. Crane dismisses the display as parlor tricks, and Abbie slips around the side as Crane tells Leeds the Hidden One will betray him. Abbie grabs the inducer and drives it into Leeds' chest, the lightning strikes, hitting the Inducer destroying the Jersey Devil.