In the conclusion of the two-part story "Attack of the Cybermen" (originally telecast on January 12, 1985), the title characters have captured the TARDIS, making it difficult for the Doctor (Colin Baker) to prevent the Cybermen from destroying the Earth with Halley's Comet. The crisis intensifies with the presence of Gustave Litton (Maurice Colbourne), a double agent in the employ of the friendly Cryons, whose own agenda is dangerously altered when he is partially converted into a Cyberman. Sarah Greene, host of the popular British TV series Saturday Superstore, makes a guest appearance as one of the Cryon women. Written by Paula Woolsey, "Attack of the Cybermen" was originally telecast in two 45-minute installments; for American consumption, the adventure was re-edited as a four-part cliffhanger. ~ Hal Erickson, All Movie Guide