The appearance of an unknown "missile-like" object in nearby space leads a European nation (unnamed, but implied to be one of the countries behind the Iron Curtain) to fire a rocket at it.

Though a patrol jet diverted to intercept the missile is destroyed by the intense heat of its drive, the pilot captures a picture of it that is then transmitted to "Conad", Continental Air Defense Command.

As Havenbrook is being evacuated, David realizes that he can use the Jove rocket to get through the missile's intense heat to destroy it, using the fission bomb "trigger" from the incomplete hydrogen warhead.

David and Joan chase after them, only to find the jeep alongside the road and the men dead from radiation poisoning after having opened the lead-lined box with the plutonium core.

The concept of the atomic-powered cruise-missile doomsday weapon was similar to that of the U.S. Air Force's Supersonic Low Altitude Missile, which was under development at the time.