Blake’s 7 is a science fiction TV show produced by the BBC between 1978–1981. Four series of 13 episodes were made over that time. It was created by Terry Nation (perhaps better known as the creator of the Daleks in Doctor Who), who also wrote the first series.
Despite its low budget, the show is held in high regard by many science fiction fans because of how it combined a dystopian setting, strong characterisation, grey and grey morality and “an enormous sense of fun” (quote from Wikipedia which did not provide a citation). The show follows a group of outlaws, called “Blake’s 7”, who are on the run from a despotic interplanetary regime called the Terran Federation. For the first season at least they’re led by an idealistic rebel, Roj Blake, but many other members of the crew have backgrounds as more “ordinary” types of criminals (thieves, smugglers, murderers…) and some are more interested in personal gain than the welfare of society.