Following my bulk-purchase of the Kristine Kathryn Rusch "Retrieval Artist" series, Amazon kindly recommended that I purchyase City of Pearl by British writer Karen Travis. (Don't read that top reader review, because it's full of bleedin' spoilers!) And, believe it or not, it's great, and I'm dead chuffed.

Like the Retrieval Artist novels, City of Pearl is set in the future (23rd century), and it involves religion and awkward relations with alien cultures and the things you are – and aren't – allowed to do on a planet not your own. There are also brilliant glimpses of the kind of future we might all have – if we continue to allow big chemical companies to stick copyright notices on the building blocks of life. Imagine, for example, a future in which all food crops are genetically modified and copyright. How does your garden grow?

(And how typical of the news media that serves us so badly that they tend to focus on the "Frankenstein"/contamination aspects of GM food and not the real reason these companies pursue it.)
A group of Christian colonists have set off to Cavanagh's star, sending a single message back to Earth: don't follow. It's assumed they've been lost, but then Shan Frankland is appointed to lead a small expeditionary force on a 150-year round trip… to do what? The key plot device here is that Frankland is confidentially briefed using smart drugs that only release information into her head piecemeal, so she actually doesn't know her mission, just that she freely agreed to it.

She spends her time with things "on the tip of her tongue", as it were, the information just not within reach of her conscious mind. She leads a group of seven Royal Marines, seven scientists, and one journalist to a beautiful almost-Earthlike planet (less oxygen, higher gravity, longer seasons), where she finds a group of humans living an idyllic pastoral life – but dwelling underground. It turns out they're only barely tolerated by the guardians of the planet, who are quite willing to erase whole cities in order to preserve the planet's ecology.

There's lots of good stuff here about the inability of humans to think of "lower" life-forms as "people," even if they're quite intelligent. And stuff about signs and messages misread, misunderstood, or not even recognised as messages. All science fiction is about the time in which it is written, whether or not it's set in the future, and it's clear that the post-2001 SF about the fate of a standard set of – problematic term : Western – values in the face of peoples who see the world through quite different filters (the metaphor here is of aliens who can see colours in what we see as clear glass) is very interesting indeed.

One of the most boring aspects of Science Fiction as it is filmed – for movies or TV – is the knee-jerk assumption that humanity is in the right. I'm so bored of the "threat to Earth" theme that it spoils my enjoyment. The greatest weakness of any SF film or TV programme is the production assumption that the audience will not be engaged unless somehow Earth and/or humanity is under threat. As such, there are never any of the real joys of SF – the creation of wonder, or the evocation of the completely alien viewpoint.

This is just one of the reasons to love Karen Traviss' City of Pearl and its sequels. Because although there are a handful of sympathetic human characters, the people you're rooting for are the aliens who are trying to deal with the peculiarly skewed morality of the humans they encounter.

This first sequel, Crossing the Line carries on the story where it left off, with former police officer Shan Frankland learning to cope with her new status as a carrier of an alien parasite that keeps her alive with miraculous healing powers, but also alters her DNA on a whim. Shan sets up house with Aras, an alien who also carries the parasite, and they begin to deal with the politics of an alien society and the strained diplomatic relations with humans and other species, and the questions raised by disputed territory and a fragile but intelligent water-based species that cannot defend itself.

The issues are both environmental protection and interspecies morality, as incompatible cultures interact. This is a well-paced genre piece that highlights – for example – the horror of a vegetarian species (who consider all creatures to be "people" – intelligent or not) when they encounter meat eaters.

More importantly, it's a cracking story with the ultimate heroine: Shan Frankland, a woman who is prepared to make huge sacrifices yet expects and receives no recognition. In City of Pearl Aras executes a human scientist who dissects an alien child (one of the protected squid-like aliens) after being specifically told not to do such a thing. In Crossing the Line the stakes are raised even higher, as some of the humans commit horrifying acts which both beggar belief and have the sad ring of familiarity.

The inevitable escalation is superbly told, and the climax is both shocking and exciting, setting up the next sequel, The World Before. I've mentioned before that Traviss hasn't got a British publisher, a ridiculous situation, but thank goodness that the internet makes that kind of distinction kind of irrelevant. It's true she writes American-style SF, but she does so in a distinctly British voice, which makes for a refreshing read. Spot on!

The third in her series set on or around Bezer'ej, The World Before continues where Crossing the Line left off. Rather than feeling like a satisfying conclusion to a trilogy, this feels like a marker on the way to somewhere else, and there are indeed at least two further sequels to follow.

It's difficult to say much about a 3rd in a series without spoiling earlier episodes, but suffice it to say that for those who have read this far, there are twists to the story that keep it getting more interesting.

For example, the humans who encounter the main aliens here, the Wess'har, learn to fear them because of their extremely strict environmental policies and their view that all beings have a right to exist without interference from others. In such a context, the proliferation of humans – even on their own planet – at the expense of other life-forms and the biosphere – comes to seem like an out-of-control infestation.

But it turns out that these Wess'har are a colony of softy liberal pacifist hippy environmentalists who left their home planet thousands of years before because they wanted to have even less impact on their environment than was culturally acceptable back home. The World Before, the place they come from, holds even more mystery, and needless to say, the home planet Wess'har turn up in this episode and seem determined to deal with the human threat by any means necessary.

There's a lovely moment in this when a Wess'har scientist resurrects a pair of parrots from a gene bank and finds them not only beautiful, but intelligent enough to learn speech. Now, think of the way parrots get treated and threatened and exploited in this wonderful world of ours and imagine what the Wess'har might think of us!

The question at issue here is actions vs. motivations. We all know about the Road to Hell, but the humans here encounter a species that doesn't care what you thought you were doing or what you wanted to happen. They make judgements based on actions and their consequences alone. There's no such thing as an accident, or collateral damage that is somehow excusable: you are responsible for your actions. Another cracking read from Traviss, and can't wait for the next instalment.