Army radiation experiments awaken a subterranean monster from a fissure that feeds on energy and proceeds to terrorise a remote Scottish village. An American research scientist at a nearby nuclear plant joins with a British investigator to discover why the victims were radioactively burned and why, shortly thereafter, a series of radiation-related incidents are occurring in an ever-growing straight line away from the fissure.

Dean Jaggeras Dr. Adam Royston
Leo McKernas Inspector McGill
William Lucasas Peter Elliott
Edward Chapmanas John Elliott
John Harveyas Maj. Cartwright
Michael Ripperas Sgt. Harry Grimsdyke
Anthony Newleyas LCpl. 'Spider' Webb
Ian MacNaughtonas Pvt. Haggis
Peter Hammondas Lt. Bannerman
Kenneth Copeas Pvt. Lansing