Charlie Crow (Dallas Roberts) is the host of a late-night radio show. His career and living standards have been declining for a long time. The ratings of the show have not increased but decreased, and he is facing the risk of being cut. He is divorced in life, and his relationship with his ex-wife and son is like fire and water. One night, Charlie answered a call from a 17-year-old boy named Jeff. The boy claimed that he was troubled by a mysterious shadow man and his spirit was almost collapsed. He then sent Charlie relevant medical experiment materials. Although Charlie regarded it as a boring prank of the teenager, Jeff's suicide by shooting himself during the connection still caused a great shock in the society. Charlie, who was accused of public showmanship, had to follow up on the matter according to the producer's instructions in order to save the ratings. In the process, the young woman who had met him once died unexpectedly, which greatly touched him. More and more witnesses of the shadow man issued statements, and a series of secret experiments that lasted for 30 years quietly unveiled the mystery...