Northern Lights is a young-adult fantasy novel by Philip Pullman. It's set in a parallel universe and features the journey of Lyra Belacqua to the Arctic in search of her missing friend, Roger Parslow, and her imprisoned uncle, Lord Asriel, who has been conducting experiments with a mysterious substance known as "Dust". A fantastic, rip-roaring adventure, beautifully written with the advantage of a TV series on the BBC. Highly recommended for children studying for the 11+