Planet M1369X, known to its inhabitants at End of the Line, was settled by a band of escaped convicts. Now, three generations later, this backwater ball of rock and its two moons are at the center of a potential conflict between the human Federation of Planets and the saurian G'rok Empire. Cullen Park, owner of Parks Parts Emporium, a space ship repair facility on the planet, and his assistant Bitsy Jacobs find themselves thrust into the roles of defenders and peacemakers. The fate of human space is in the hands of a ne'er do well and a youthful mechanic, who must contend with an exotic alien race whose customs and intentions they are ignorant of, and an officious human bureaucrat whose motives are even more opaque. As the clock ticks down to a potentially deadly confrontation, Cullen must use his wits-for he has no other weapons-to save his planet from certain destruction.