The Saskias, Saskia Chandler and Saskia Hunt, are off on holiday to America. But before they go they have a few things to attend to, both as the SuperTwins, Kyra and Katya, and as themselves. Saskia Chandler discovers she needs to use the knowledge and experience gained when she was still Richie and worked in IT to unravel a mystery involving robberies from ATM machines. Saskia Hunt seems to have come to terms with just exactly who Saskia Chandler actually is, now it's just up to Saskia Chandler to come to terms with that for herself. The Twins find themselves shunted backwards and forwards in time, sometimes only a little way, sometimes hundreds of years - and once into a timeline that has no beginning - and no end. Despite trips to the Moon and to Houston, this time with Rio to assist them, eventually they get to go on their holiday. But they find they still need to use their super powers as they get dragged back to Britain to prevent the whole of South East England becoming an uninhabitable wasteland. Perhaps the strangest thing of all happens in Chicago when they meet two men who were deadly enemies - in the nineteen twenties. But there's a problem - they have no means of returning to their own time!