Linked to a BBC1 television series, this is an account of sexual reproduction in the animal world, culminating in the question of why there should be sex in the first place - the ultimate driving force of evolution, but also selfish, aggressive, competitive, and sometimes fatal. The meeting of mates, the sexual act, and the consequences of producing offspring, forge an alliance between males and females that is rife with tension and distrust. The two sexes tactically play games with each other to get the best return from mating: at stake is the greatest reward for any animal on earth - the generation and survival of their progeny. The drive to succeed in this gives rise to a violent, beautiful and spectacular show of animal behaviour, captured here through the book's colour photographs.