In Hinwil in the Zürcher Oberland I asked friends about their favourite place around the Bachtel. Without exception they told of “their” waterfall from their childhood. I followed these places and over months documented these waterfalls by day — after thunderstorms, floods, or in summer after dry spells. Then I shifted focus and set out into the night, pursuing the riddle of twilight phenomenologically. It is the mixture of many small components that makes these twilight images possible: a cold wind must blow, the moon shine, it should rain and storm at once, the falling water be very cold. But even when all conditions are met, there is no guarantee the lights appear; their span never exceeds 15 minutes. For this book I took 12,000 shots, not one edited or cropped — I only pressed the shutter. I chose the images that came closest to my inner pictures and to the drawings and paintings of recent years. On these excursions by day and night my husband John accompanied me everywhere, securing me so I would not fall down the slippery rock face. I did not try to photograph fairies, gnomes or spirits; that they nonetheless showed themselves is one of nature's mysterious gifts. To examine twilight is mystical: the day dies, the night is born.