Fans of science fiction TV are used to their favourite shows being ignored or ridiculed. If you were to go by broadsheet column inches, you'd think everybody was glued to Mad Men, whereas the drama barely makes a dent in terms of viewing figures. Small-screen science fiction tends to be low-profile, despite the fact that it's enjoying something of a renaissance right now. Here are three of the best current offerings.

Falling Skies

This Steven Spielberg-produced alien-invasion drama has made it to a third season; impressive for a show that no one ever seems to talk about. The first run was patchy but showed promise; the second was much better. Now, we're promised all-out war between the human surivors based in the ruined city of Charleston and our alien overlords, the Espheni. Last season ended with the arrival of another alien race, the Volm, whose homeworld was destroyed by the Espheni, and they are offering to help the humans get rid of them. But are these new aliens all they seem? There's still a lot that's clumsy about the show (both in the plotting and acting), but it's hard not to to get involved in the drama when the future of the planet is at stake. A fourth season is already in the pipeline.

Continuum

This was heavily advertised when it first arrived on Syfy and ended up being one of the more pleasant surprises in recent years. Part time travel adventure, part police procedural, Continuum improved as it progressed, getting smarter each week. Cop Kiera Cameron is accidentally sent back to our time from the year 2077 when a band of freedom fighters, Liber-8, use a time-travel device to escape "justice". She joins up with the local police force and helps them track down the Liber-8 members, who are now trying to prevent their futures from happening. Rachel Nichols, who plays Cameron, puts in a winning performance. As the show progresses, we learn that the "terrorists" have some legitimate complaints, and Kiera begins to doubt the honesty of her future leaders, making it one of the few shows to comment on the ruling 1%. And it's nice to see a show shot in Vancouver (as plenty of US shows are) that actually is set there.

Defiance

Defiance has had little fanfare, despite getting enough viewers to warrant a second season. Set decades after the arrival of seven different strains of alien species, the Votan, it's perhaps the boldest of the bunch. In terms of world-building, there's a lot to take in. The planet is populated by the now co-existing survivors of a lengthy humans-v-aliens war, a war that left the planet scarred and half-terraformed (or whatever the Votan equivalent is). The action takes place in the small frontier mining town of Defiance (built above the ruins of St Louis). Among the main players are the Castithans, a pale, long-haired, ruling-class race with plenty of peculiar traditions (members of a Castithan family take baths together). The AV Club dubbed them "the space Lannisters", and it's hard to find a better description than that. There are the even paler Indogene, the colder, more scientific breed represented by the enjoyably brusque Doctor Yewll. Then there's the more feral, bronze-hued Irathient, largely represented by Irisa, a youngster raised by her human stepfather, the town's lawman ex-marine Joshua Nolan. It takes several episodes to get the lay of this new land, but it's worth it, for the power struggles, secret plans, ancient artifacts, war criminals, betrayals and murders, as well as the inventive alien cultures. After a nicely brutal season-one finale, a second season is in the works.

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