 The mythical blue men may have been part of a tribe of " fallen angels " that split into three ; the first became the ground dwelling fairies , the second evolved to become the sea inhabiting blue men , and the remainder the " Merry Dancers " of the Northern Lights in the sky . The legendary creatures are the same size as humans but , as the name implies , blue in colour . Writer and journalist Lewis Spence thought they were the " personifications of the sea itself " as they took their blue colouration from the hue of the sea . Their faces are grey and long in shape and some have long arms , which are also grey , and they favour blue headgear ; at least one account claims that they also have wings . The tempestuous water around the Shiant Isles 19 kilometres ( 12 mi ) to the north of Skye , an area subject to rapid tides in all weathers , flows beside the caves inhabited by the blue men , a stretch of water known as the Current of Destruction owing to the number of ships wrecked there . 
