Triplanetary is a science fiction novel and space opera by E. E. Smith. It
was first serialized in the magazine Amazing Stories in 1934. After the Lensman
series was published, Smith expanded and reworked the novel into the first of
two Lensman prequels (the second prequel was a new original novel, First
Lensman). It was published in book form in 1948 by Fantasy Press.
The novel covers several episodes in an eons-long eugenics project of the
super-intelligences of the Arisians. This alien race is breeding two genetic
lines to become the ultimate weapon in Arisia's cosmic war with their arch
enemy, the Eddore. The initial chapters cover the Kinnison genetic line during
the fall of Atlantis and Nero's (Gharlane of Eddore) reign in Rome. These tales
were inserted into the novel following the serialized release, along with
chapters covering members of the Kinnison line in World Wars One, Two and
Three.