Warped by the twisted effects of Strontium 90 fallout, mutants are a victimised underclass on Earth. Denied normal work, many have taken on the one job that is too dirty for norms: bounty-hunting. Across the vast frontier of space, they hunt the criminals too dangerous for the Galactic Crime Commission.

Strontium Dog, Johnny Alpha is hot on the trail of crime lord Mister Grinn after a chance encounter with a small-time crook reveals a tantalising lead. Accompanied by a mismatched group of mutants, Johnny must contend with an all too real doomsday prophecy as well as Grinn's many henchmen, if he is to bring in his man – dead or alive.