'How long do you think they'll keep looking for us?' I asked Lee, as we lay there.

'Until they find us,' he answered grimly. They came in summer. They fell upon the land swiftly and suddenly. Through autumn they spread, like locusts, like mice, like a plague.

Now it's winter. They're still here.

But so too are Ellie and Homer and their friends. Half-a-dozen teenagers with all the odds against them. All they have going for them is their friendship, and their own inner spirit.

How far can courage go? What do you save first when you're fighting for everything - yourself, your friends, your family, your country?