PLAYED BY: Jeanne Bal
SPECIES: Human Female

In 2266, Captain Kirk led a landing party to the surface of M-113 to perform the routine medical examinations required of all scientific expeditions. On the planet, the landing party encountered who they thought was Nancy Crater. What the landing party saw was actually the M-113 creature impersonating Nancy Crater. Each member of the landing party saw a different woman, although they weren't aware of that.

PLAYED BY: Bruce Watson
SPECIES: Human Male

Green beamed to the surface of M-113 with the second landing party, where he was killed while searching for Nancy Crater, when his body salts were devoured by the M-113 creature.

PLAYED BY: Michael Zaslow
SPECIES: Human Male

Crewman Darnel, was part of the original landing party on planet M-113. He was assigned to help with routine Medical checks with Doctor McCoy. He was the first victim by the salt creature in the form of Nancy Carter.

PLAYED BY: Alfred Ryder
SPECIES: Human Male

Unknown at the time of the Crater expedition, a single surviving member of the "salt vampire" race continued to live on the planet. It eventually killed Nancy and continued to live along with Robert until 2266. When the USS Enterprise visited for a routine check, Crater was visibly upset and wanted them to leave. When it was discovered that a creature was killing them, James T. Kirk and Spock tried to apprend him.