Locke & Key: Breaking down what the keys are and what they do

Ghost Key

The Ghost Key can only work on the Ghost door located in the winter study in Key House. When inserted into the door, the user of the key leaves their body and becomes a ghost.

Nothing happens to their body, as long as the door is open, leaving the ghost to roam or fly over the grounds of Key House.

The ghost cannot be seen by anyone, except fellow ghosts. However, they can witness events and retain what they have seen and heard once they return to their body.

The Ghost door is essential to the survival of the host body—once the door closes, the ghost becomes trapped as a ghost, and their body dies.

This happens to Sam Lesser (Thomas Mitchell Barnet) when he accidentally goes through the Ghost door with the key in it, and the door is closed on him. His body is dead—for all intents and purposes—and Lesser is now trapped as a ghost forever, doomed to roam Key House with no end in sight.

Head Key

One of the most creative keys in Locke & Key, the Head Key allows the user and anyone in their vicinity to see the inside of their mind. On the show, the interior of the mind takes on the form of the person’s favorite place—for Bode (Jackson Robert Scott), an arcade, a shopping mall for Kinsey (Emilia Jones), the Seattle home for Tyler (Connor Jessup).

In the comic books, the Head Key made the top of a person’s head open so people could peer into their minds and see miniatures of their memories and feelings. In the show, the feelings are life-sized renditions of the person—Kinsey’s fear appears as a monstrous version of her.

Using the Head Key, one can remove or add elements to one’s mind—Duncan Locke’s (Aaron Ashmore) memories were removed from his mind, and presumably the same was done to Erin Voss (Joy Tanner).

Tyler successfully added books about Matheson and England to his mind, and in the past, Rendell Locke (Bill Heck) had stored the Omega Key inside his mind for safekeeping.