The story of two fifteen year old girls who live in the same house but forty-five years apart. By some strange set of circumstances, they cross through each other's space while climbing the staircase, and get switched into each other's time. So Sarah finds she has gone back to nineteen seventy-four, and Sally lands up in the future. Both have strong reasons for wanting to get back to their own times, but how to do it? Perhaps there is a friend who could help.