<p>It is the summer of 1851 and Charlotte Morrison is on holiday in Germany with her brother and his wife. Charlotte may be a spinster aunt with a seemingly sparse life, but beneath that quiet respectability lie unsuspected depths.<br><br>Boating down the Rhine one day, Charlotte sights a fellow traveller, who releases the hissing floodwaters of her subconscious. Dark and dangerous, they sweep Charlotte towards the watershed of her life, stretchi...