A reluctant hero, afraid of his shadow, travels through darkness discovering new and fantastic worlds. Six year old Clifford Tuttle disappeared while on expedition in South America with his parents and was found over 1,000 miles away three days later with no memory of what happened. Now fourteen, Clifford lives in the dark, hiding away from the light, terrified of his own shadow. In his search for answers he is drawn back to the light where he discovers that his shadow casts a gateway allowing him to travel to strange and fantastic worlds. As Clifford learns more about his abilities, he meets others like himself and together they all fall into perilous adventures and the realization that the fate of all these new worlds, including Earth, balances on his shoulders.