Guest Stars Mitch Pileggi as Assistant Director Walter Skinner Nicholas Lea as Agent Alex Krycek Steven Williams as Mr. X Tony Todd as Augustus Cole Jon Gries as Salvatore Matola Co Starring William B. Davis as Cigarette-Smoking Man Mitchell Kosterman as Detective Horton Don Thompson as Henry Willig Michael Puttonen as Dr. Pilsson Paul Bittante as Lt. Reagan Anna Hagan as Dr. Charyn Claude De Martino as Dr. Grissom Dave Adams as Dr. Girardi