An eastbound freight train was carrying hazardous chemicles on board when it suddenly lost its brakes & whent out of control aventulley they discoverd a deadly secret about the runaway it was carrying a russian made atomic bomb and NTSB agent john seger has to go stop the train before it reaches denver colorado and explodes. A waste disposal company has a Russian nuclear bomb to transport, and an employee decides to save money by concealing it on a freight train. The train, also loaded with hazardous and flammable chemicals, suffers a brake failure and becomes a runaway heading for Denver. A wreck world be bad enough, but mush, mush worse if the bomb goes off. A heroic NTSB investigator boards the train; he and the railway man try various ways to stop the train, but nothing works. Meanwhile Denver residents are struggling to collect their families and then leave town, despite rioters and gridlock. Will the train have to be derailed to stop it? If it does derail, will the bomb explode, and if it does, what then?