The Story Trap - The Sisters, #1

A contemporary fantasy set in Cape Town, South Africa. Rebecca never expected to meet a witch, least of all in a second-hand bookshop in Mowbray. Surely she had nothing to fear from an old lady holding a box of children's books. But on the train home Rebecca collapses and is rushed to hospital, deep in a coma. Rebecca's sisters, Pippa and Anmarie, are confronted by a frightening mystery: her body might be in the hospital bed, but where was Rebecca?---Rebecca stared out of the train window.
How could it be dark already? She had been on the train home, reading in the familiar crush of the rush hour commute. Now the carriage was empty and outside impossibly tall buildings stretched up towards the night sky. She was alone in a strange world. Somewhere close by, an old woman watched, and waited. The trap had worked and her quarry was caught. Now all she had to do was keep Rebecca dreaming.