Entangled - Hancock, Graham

When a drug overdose causes Leoni, a troubled teen from twenty-first-century Los Angeles, to have a near-death experience, her soul is lifted from the modern world and flung into a parallel time 24,000 years in the past. There her fate becomes entangled with that of Ria, a young Stone Age woman fighting for her life against the ferocious Illimani, an army of evil led by the vicious Sulpa, a powerful demon determined to destroy humanity.As the invaders annihilate Ria's people, inflicting torture and human sacrifice, Sulpa moves ever closer to his ultimate goal: to manifest physically in the twenty-first century and condemn all of mankind to perpetual slavery. The hour is late and any chance of stopping him seems lost. But there is still hope, if Leoni and Ria can rise to the challenge fate has set them. Uniting outside the flow of earth time, they must venture forth into regions of wonder, master their own deepest fears, and fight battles they could never have prepared for, if Sulpa is to be defeated...