Then in this Archaean microbial age, some unicellular visionary made an explosive discovery—akin to mankind’s discovery of fire, in terms of its impact. A volatile, poisonous chemical was tamed. Since the dawn of the Earth, this chemical had voraciously attacked any element it came into contact with; now it became the servant of developing life. This first metabolizing of oxygen might have been a defence mechanism. A process that incorporated the dangerous substance rather than falling prey to it. Perhaps your ancient ancestors took wolf cubs from their mothers with a similar goal. And what a world of opportunity opened up! Oxygen is a shortcut to a higher energy lifestyle, a ticket to getting out of the bacterial ghetto to live the high life. Our cast of characters becomes more complex as a result. Life gets a new paint job, alloys and go-faster stripes, now there is something more powerful under the hood.

Next, single cells find advantage in numbers. Simple bacterial mats carpet the floors of every sea, shore to shore, washing up on lifeless beaches in a scummy slick of organic matter that cannot even decay properly yet. Then cells cling to each other, sharing the work so enough of them might even resemble some larger coherent being. But the next storm or riptide breaks them down again, to reform slowly, later. Some developing cells cling to those bacterial mats and rocks and sieve the water for organic detritus; some drift in the current. Cells evolve that can only survive in the company of their fellows, doing some small specialist role like an office worker who only deals with form G. But because the rest of the alphabet is also monitored, the paycheque still comes through every month. Multicellular life evolves exponentially, now it has that hard, oxygenated liquor to fuel it. Everywhere, a garden of life arises—the very first Eden. But it doesn’t support life like ours, or even our ancestors’. This is life of another caste entirely. A world of quilt-bodied things that lie supine upon the sea floor, or inch slowly across the bacterial mats without limbs or muscles, feeding upon them without mouths. They are a global community of organisms alien to us, and they live without tooth or claw, without eyes, without organs.

Our world was like this once. Go back six hundred million years and you wouldn’t know the difference. But this is not our world.

In this world, something awoke.

PART 1

DOWN THE RABBIT HOLE

1.

Her name was Lee, short for Lisa Pryor. Which, technically, was short for Lisa Chandrapraiar. But when her grandparents came to England from Pakistan, the immigration authorities had been having a rough day and so Pryor was what went on the paperwork. Her parents still called her Lisa, but Mal called her Lee and that was the important thing. After a while her other friends did too, because what Mal said tended to stick.