Charles Rangeley-Wilson journeys across the world to locate unusual fish and the stories behind them. In the early 1900s brown trout were introduced to Bhutan's rivers from a Scottish loch and it is here that Charles travels, hoping to find his fishing Shangri-la. His permit granted by the King allows him a week's fishing and he tries the beautiful spring-fed stream of the Gangtey Valley and on to the torrential Tang River, the most sacred in Bhutan.