Kolchak tries to find some kind of reptilian monster that has been killing construction workers after they open a new tunnel, nearly 2 miles underground.

Cast: Darren McGavin, Simon Oakland, Kathie Browne, Albert Paulsen, John Hoyt, Frank Marth, Tom Bosley, Cliff Norton, Frank Campanella, Margaret Avery, Lew Brown, Keith Walker, Bill Deiz, Greg Finley, Tom Moses