Courtesy of BBC

The premise of Blake's 7 (BBC, 1978-81) held nothing remotely original. The outlaw group resisting a powerful and corrupt regime is an idea familiar from Robin Hood and beyond. Even the evil Federation's brutal soldiers were little more than Daleks in human form - unsurprising, since the show's creator, Terry Nation, also devised Doctor Who's most popular adversaries.

Blake's 7's triumph lay in its vivid characters, its tight, pacey plots and its satisfying realism. The original septet was led by Roj Blake (Gareth Thomas), a swashbuckling idealist framed for child molestation, who was wonderfully counterbalanced by Kerr Avon (Paul Darrow), a cynical and self-serving fraudster whose dictum that "No good deed goes unpunished" summed up the show's philosophy.

Paul Darrow encapsulated the spirit of the series when he described it as "Realism in an unrealistic situation". Heroes were killed off, the evil Federation would often crush the rebels, and major elements of the show's iconography, such as Blake's original spacecraft, Liberator, were spectacularly destroyed. For arguably the first time since the 1950s Quatermass serials, the BBC had created a popular sci-fi/fantasy show along adult lines, and its success - often achieving ratings of over ten million despite being pitted against Coronation Street - led to series such as Star Cops (BBC, 1987) and Invasion: Earth (BBC, 1998). The end-of-season cliff-hanger was another innovation, with the 'let-them-dangle' device now common in both UK and American series.

Aside from Avon, only two characters were ever-present throughout its four-year, 52 episode run: cowardly class-clown Vila Restal (Michael Keating), and the improbably glamourous arch-villain Servalan (Jacqueline Pearce) - a compelling contradiction: feminine and alluring, but merciless, murderous and driven by a mania for power.

Blake's 7 was inspired by the global success of Star Wars (US, d. George Lucas, 1977), but the programme worked best when the dubious special effects were put aside and character interaction came to the fore. Established sci-fi writers such as Robert Holmes, Chris Boucher and Nation himself were aware of this, crafting classic episodes like 'Rumours of Death', 'Orbit' and the climactic 'Blake'. Ultimately, the one force the rebels could not overcome proved to be the BBC's long-standing apathy towards science fiction. However, the bloody finale, in which Avon murders Blake, exemplified the programme's strengths - fearless narratives, credible but surprising character development and an enormous sense of fun.

Gavin Collinson

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