Earthfall by Mark Walden

Bloomsbury, 2012. Earthfall is the first book in a new series by Mark Walden, the author of the popular Hive series.
In an eerily deserted London, a solitary boy flees for his life, his enemy a fearsome creature like a mechanical jellyfish with amazing strength. He is saved from death by the intervention of an armed girl, the first human he has encountered in 18 months.
Who is the mysterious girl? What has happened to the previously thriving human population of London?
The boy and his new friend, Rachel, are attacked by a second fearsome creature, a Grendel, and this time their lives are saved by a human known as Jay. Jay and Rachel, the boy discovers, are part of a small group of humans, fighting for survival and also waging war on the invaders.
This is a fast paced novel, with an imaginative but seemingly logical explanation for the disaster that has befallen not only London but other cities on Earth. Walden quickly sets the scene, vividly and economically creating characters to whom we can relate. Each chapter leaves us wanting more, the story carrying us along to an alarming conclusion. As we reach the end to this adventure, we know that we are promised just as much action in the sequels to come.
Any lover of adventure will enjoy this story, whether male or female.
Thelma Harvey