0 7445 2449 0. New World.By Gillian Cross, Oxford Pounds 9.99. 0 19 271723 5. Molly Brown’s Virus is set in Chicago in 2078. The ozone layer has gone entirely, Moscow is the entertainment capital of the world and the bulk of humanity has been wiped out in the One Day War. Those who remain are mostly sterile and maintain the illusion of youthful population by recourse to anti-aging techniques - the boy next door could turn out to be 50 - relying on robots to perform essential services. Two genuinely young people, Amanda and Steve, hold down jobs at an archaic outfit where the workforce, glad to have any form of gainful employment, waste little time wondering what their employer actually does or makes.

The rest of the staff are not very well; a highly contagious disease is picking them off, while some other kind of malady is attacking their computers - but these machines are at least recognizable as computers. Mingling with these, another life-form is at large, the computers with artificial intelligence. Ostensibly annihilated in a kind of Night of the Long Knives, when all such machines were commandeered and destroyed, some have nonetheless survived - the ones with apparently human bodies and real human brains.

If you stop to think about it the story is full of holes and unanswered questions - who precisely occupies the Oval Office is one -but it is not fatuous, delivers a good read, plenty of horrible surprises, a neatly undermined happy ending and even a few laughs.

To Trust a Soldier takes place in England at possibly a similar time in the future. People have reverted, for some unspecified reason, to an agrarian society without machines, although they do have guns. From somewhere abroad an invasion is launched, civilians flee before the invaders and men leave their shops and farms to repel the enemy.

A hired girl, Mary, left behind on one farm, falls in with a band of men she takes at first to be the enemy. They turn out to be her countrymen, volunteers, eager to defend their land and led by Mr Talbot, a regular soldier who is taking them to the battlefield.

Lost and lacking a map they conscript Mary into guiding them. An understanding swiftly develops between her and the youngest soldier, Hobbs, but the more intriguing figure is Talbot who, it becomes clear, is leading his men not into battle but out of it. He has seen active service overseas and knows what happens in war, having seen his own son maimed and traumatized at his side.

When the truth emerges the volunteers are not grateful. They want to fight, they insist on being led to the slaughter and patriotically turn in Talbot as a deserter, unaware of what is likely to happen to him at the hands of the military authorities. All this rings horribly likely; what it lacks is a sense of reality. “Somewhere in England” is about as close as it gets to a theatre of operations, the future it depicts is amorphous. Why are there no machines? Who are the enemy? Where is the Government? Reading at a time when England has never been more governed, one notices the vacancy, the more so because it is impossible not to expect the questions to be answered in the course of the narrative.

This is another absorbing read but it seems likely to leave the reader feeling not so much short-changed as inattentive; what have I missed? Human relationships require only other humans in order to flourish, but patriotism needs a country. It may be called England but it doesn’t seem to be there.

New World, by Gillian Cross, deals with the nastiness of the here and now. Miriam and Stuart, two teenagers, are selected, apparently at random, to test a computerized virtual reality game - New World - developed at a cost of millions and ready to go on the market. So much is invested in its success that they can readily understand why they are sworn to secrecy and forbidden to meet each other to discuss it. Playing in separate locations they meet only in the game, proceeding from co-operation to competition and then to conspiracy as it begins to dawn on Miriam that they are no longer alone in their virtual reality; someone else, who ought not to be there, has hacked in and is attacking both of them.

But there is no thought of backing out; the game is addictive, as it is meant to be, but it is also terrifying, surely more terrifying than necessary, and suspiciously reminiscent of the players’ own phobias and nightmares. In fact, without this element it would be fairly banal, as Miriam begins to discover. So what is it exactly that they are testing? Clearly not the game itself. When they discover the answer it only serves to raise even more questions, leaving Miriam and her new companions to deal with real reality, when the helmets and gloves are off and they meet face to face.