A lieutenant on the Enterprise-D whose partner, Daniel Kwan, kills himself in 2370, and who then appears in the vision Deanna Troi has while investigating.
Lieutenant Maddy Calloway serves on the USS Enterprise-D. She appears in the episode Eye of the Beholder, played by Johanna McCloy.
She and Lieutenant Kwan had been close and were planning time together when he leapt into the plasma stream of a warp nacelle. Calloway is shocked and can offer no reason. She tells Troi that he had been cheerful and had nothing troubling him that she knew of.
When Troi visits the place where he died, a psychic trace left there years before sets off a long hallucination. In it Troi and Worf become lovers, and she then finds Worf laughing with Calloway and kills him out of jealousy. None of this is real. The vision repeats an old crime, a murder done during the ship's building, with the faces of Troi's shipmates filling the parts.