A space capsule escape pod from the Endeavor II, a manned mission to Jupiter which mysteriously disappeared fifteen years ago, returns to Earth with Lieutenant Green's father, Commander Lewis, aboard. Believed lost, he wastes no time catching up with his daughter, but when he arrives for his debriefing at the International Space Agency, he is revealed as a Mysteron agent and takes Green hostage inside a bunker containing an antimatter reactor that is rigged to blow, leaving nothing but a smoking hole from California to Texas and taking 8 million people with it.