A tannis root is a made-up herb’s root that appears in the 1968 film “Rosemary’s Baby” and is kept in a locket. In the film, a character by the name of Terry has the tannis root wrapped in a necklace that the Castevets gave to her. The tannis root was described as being enigmatic, poisonous, and smelling.

The movie’s main character, Rosemary, appreciated the locket Terry was wearing that had a piece of tannis root. Later, Terry would commit suicide, and the Castevets would give Rosemary her locket while claiming it was a lucky charm.

Roman Polanski directed the horror movie “Rosemary’s Baby,” which stars Mia Farrow in the title role. The movie was adapted from Ira Levin’s book of the same name.