The ninth episode of the first season of Torchwood, “Invisible Eugene,” is full of poignant double entendres and symbolism. The title itself reflects the life of an individual who, after failing in a math competition, was abandoned by his father and ignored by most people as he followed a trajectory that involved entering into possession of an alien eye and waiting around for something interesting to happen – presumably when the alien returned to claim it.

As his father leaves him and his family, Eugene says about the eye, “If you leave something important behind, you come back for it, right?” The meaning in relation to his father’s departure is hard to miss.

The episode thus highlights the potential for interest in aliens and other geeky pursuits to serve as distractions and sources of comfort for the lonely and socially maladjusted. It mentions people visiting the local video store in the hope of being “transported away,” and what a shame it is when a brief human life span is spent waiting around in the hope that something interesting will happen.

But in addition to its point about the invisible nerdy people blending into the background in schools and at work, dreaming of amazing things but not making amazing things actually happen in their lives, this episode also enters another domain that is surprisingly prevalent in science fiction.

The soul.

Eugene hangs around as an invisible presence after he is killed in a car accident – because he swallowed the alien eye. But the possibility of the personality of an individual surviving their death, even if only with the help of alien technology, is still remarkably prominent in science fiction, given that it is an idea with little or no basis in anything genuinely scientific. Whether on thinks of Fringe or Lost, or Doctor Who, Star Trek or Star Wars or Battlestar Galactica, all seem to leave room for the possibility of transcending death, of surviving, of the immortality of the soul. Even Torchwood, in which Capt. Jack Harkness, who is somewhat unique in having died, says in the very next episode, “Out of Time,” that “You don’t get reunited. It just goes black.” The very fact that Suzie and Jack and various others could return from the dead requires that something of them survive.

Many fans of science fiction would dismiss traditional religious teachings about an afterlife. Torchwood seems to want to explicitly deny that there is an afterlife. How then are we to account for the prevalence of the soul in sci-fi, even on Torchwood?

Perhaps it is because these aren’t really two themes in the episode “Invisible Eugene” after all, but only one: even a relatively “invisible” life which never achieves “greatness” is still something we recognize as so valuable, unique, and precious, that it is hard even for materialists to accept that it simply vanishes, that it is fully and truly ephemeral.