The miniseries begins in 1987. At the height of the Cold War, two US airmen monitor their radar screens at a quiet and remote NORAD facility in Alaska. Suddenly, one of the bored operators notices an unexpected blip on his radar screen. It appears to be an unidentified aircraft sneaking in on the leading edge of a weather front. He alerts his partner about the threat and begins to contact Elmendorf AFB. The other airman retrieves a silenced pistol from his desk and kills him. He then proceeds to shoot the remaining station personnel while they are sleeping in their bunks. Lighting a cigarette, the traitor notifies Elmendorf that the station will be out of commission for the next hour in order to repair a malfunctioning generator. The necessary blind spot has been created.
Next, the Soviets launch a secret incursion into Alaska. The Soviets have inserted a cold weather special operations assault force of approximately 35-40 KGB desant ski troops, with a track-driven armored vehicle, into northern Alaska. Their orders are to seize control of a strategically located pumping station along the Trans-Alaska Pipeline so as to threaten placement of floating explosive devices in the stream of oil. This operation is being conducted in response to America's grain embargo of the Soviet Union, just as the 1980 grain embargo was in response to the 1979 Soviet Invasion of Afghanistan. The governments of Canada, Australia, and Argentina have joined the U.S. in the embargo. This has caused severe food shortages and domestic unrest inside the Soviet Union. A small company-sized force of lightly armed soldiers of the Alaska Army National Guard and Alaskan Scouts, who are on a training exercise, discover the presence of the Soviet invaders. At Fort Wainwright, Colonel Jake Caffey (David Soul), a combat veteran of the Vietnam War, is sent by his commanding officer to locate one of the groups of soldiers, who have already been ambushed and killed by the Soviet assault force. Colonel Caffey takes command of the Guardsmen when his senior officer, who did not believe the news of the invading Soviet troops, is killed in the first encounter with the Soviets. Caffey notifies his chain of command by radio.
Upon learning of the situation, the U.S. President Thomas McKenna (Rock Hudson) orders Caffey's National Guard troops to be federalized and orders Caffey to do all he can to stop the Soviet troops. The President orders a media blackout on the emergency but then orders U.S. forces to be mobilized in response to the Soviet incursion, under the pretext of unscheduled training exercises. The President fears that the people of the United States will demand a declaration of war against the Russians for this attack. Fierce winter weather is preventing U.S. military units from bases and forts in southern Alaska from reinforcing Caffey's unit. Caffey deduces the Soviet assault unit's goal. He uses the few U.S. Army helicopters at his disposal to move his unit to a new pumping station ahead of the Soviets.
Meanwhile, in the Soviet Union, Soviet Premier Gorny (Brian Keith) has learned that the Soviet military and KGB leadership have executed this plan without his permission. He is informed of the U.S. mobilization and he orders Soviet forces to a similar posture. In Alaska, Colonel Caffey realizes that his men have an inadequate supply of ammunition, grenades and mines. He sets up a defensive perimeter around the pumping station making use of surplus lengths of large-bore oil pipe to establish a position from which to ambush the enemy. The Soviet troops approach the pumping station, unaware of the American soldiers' presence until they trigger U.S. land mines buried in the snow. The Soviets suffer casualties and fall back, but continue to surround the buildings. The U.S. President and Soviet Premier secretly meet in Iceland to negotiate an end to the crisis. They are unable to reach an agreement and both return to their countries, but promise each other that talks will continue.
America responds to the Soviets' continuing mobilizations, as officials recognize they are consistent with a fictional contingency plan called Красный Флаг or "Red Flag." The U.S. President orders all American ballistic missile submarines, surface warships, B-1s, and B-52s to deploy in readiness for war. He directs U.S. bombers to fly continuous paths just outside Soviet airspace. Colonel Caffey and his soldiers continue to repel the Soviet attacks on the pumping station, but his soldiers are running low on ammunition and supplies. President McKenna contacts Caffey by radio and asks him and his soldiers to hold out at all costs, hoping that the weather will break so that reinforcements can be sent to relieve them. McKenna still holds out hope for a diplomatic solution. Premier Gorny also hopes for a negotiated settlement to the crisis. However, hardline, pro-Soviet members of the Communist Party and the KGB—who remain incensed by the food shortage—suddenly launch a coup d'etat. They use a car bomb to assassinate Gorny while he is visiting the school attended by his young son, Sasha.
In the meantime, the Soviet troops in Alaska launch a final assault on the pumping station; however, the Soviet commander, concerned about the rapidly-growing prospect of nuclear war, requests a parley with Caffey. After an emotional conversation, the two men agree to discontinue the fighting. However, at that moment, one of the Soviet troops—perhaps an undercover KGB asset—suddenly hurls a grenade, which kills both men. The situation collapses in bloodshed, with a sergeant of the Alaskan Scouts managing to send one final message that the last American position is being overrun. Receiving this news, President McKenna calls the Soviet leadership and discovers that Gorny is unavailable to speak with him. The Soviet leadership claims Gorny has been felled by severe intestinal flu and that their forces will withdraw to pre-crisis positions, but McKenna does not believe them and realizes that pro-war elements of the KGB are seizing control of the Soviet Union. Once the telephone conference ends, McKenna submits to the National Security Council his belief that Gorny has been killed and that total war is imminent. He is correct, for at that moment, the coup leaders decide on an all-out nuclear strike, some of them mistakenly believing that U. S. law requires the President to obtain Congressional approval before an American nuclear attack. But President McKenna has already deduced the enemy strategy. Horrified and nearly in tears, he concludes the situation is unrecoverable, and orders a full nuclear counterstrike upon the Soviet Union.
The film focuses on a number of Cold War themes, including brinksmanship, political loyalty and the mutual distrust of both sides as they attempt to resolve the issue diplomatically while escalating their military alert levels to force the other side to back down.
The cast included Rock Hudson as the President of the United States, Brian Keith as the Soviet Premier, and Cathy Lee Crosby and David Soul as American military officers, as well as Jeroen Krabbé, Robert Prosky, Katherine Helmond and James Hampton.
A novelization of the teleplay, but differing from the miniseries as aired in several key respects, was written by Harold King under the pen name Brian Harris. Its 1981 publication by Pocket Books anticipated the airing of the miniseries by several months. It is undocumented whether the changes were King's, or reflected an earlier draft of the script, but based on a comparison of text to broadcast teleplay, it seems likely that the liberties were mostly the novelist's deliberate variation.