Super Powers

When Dave Gibbons was working on Watchmen with Alan Moore, he suddenly realized that the series was not conventional superhero fiction but an sf alternative history in which some costumed adventurers fought crime and one man gained superhuman powers. The artwork and colouring were toned down to reflect this changed perspective. 

Superheroes have their roots in sf. Superman is extra-terrestrial. We can find sf characters with extraordinary powers. Wells wrote The Invisible Man. Stapledon wrote Odd John. Poul Anderson has mutant immortals, mutant time travellers and a universal telepath. There are similar characters in works by Larry Niven and Julian May.

Superheroes have become a separate cinematic phenomenon but do not forget their sf roots.