by Hal Erickson
synopsis
Invited to visit the country estate of a renowned historian, Cathy discovers that her host has vanished and that his highly suspicous ward (Janine Gray) has taken his place. Before long, Cathy finds herself being stalked by a shadowy assassin. Will Steed arrive in time to save Cathy from a grisly fate -- and just who is her mysterious assailant? Written by Brian Clemens, "Don't Look Behind You" was first telecast in England on December 14, 1963. American viewers who saw the episode for the first time on March 19, 1991 would recognize guest star Janine Grey for her appearance on two other "cult" spy series, The Man from U.N.C.L.E. and Get Smart.