Neal "Storm" Cloud failed his Lensman exam, but life has a strange way of making hero of even those who sometimes fail. Cloud's family is tragically killed when a misguided attempt to blow out a vortex lands one of the fragments right on his house. Devastated by the loss of his family, Cloud takes a leave of absence from the Radiation Lab where he works studying the vortices. As he drives he is struck with an idea for "blowing out" a vortex. It is slightly technical (Smith explains it so it can be easily followed), but the general idea is that Cloud's brain works so fast that he can calculate exactly where the center of the vortex will be at a moment in time and how big an explosive is needed, then hit it with a bomb that is set at the exact strength to actually extinguish the vortex instead of blowing it apart and making more vortices. As it continues the book tells of Cloud's new job as the universe's one and only vortex blaster. This job takes him from planet to planet where he blows out vortices, matches wits against drug dealers and gangsters, meets new life forms, and acquires a crew for his small scout ship. His adventures are many and varied, and the lifeforms he meets are strange and interesting.