Jake Chambers (Tom Taylor), aged 11, has some visions involving a black man looking to destroy a tower and bring the whole world to ruin, and on the other hand is a gunman trying to hinder them to put his plan in place. The mother of Jake, his stepfather and the psychiatrists who consulted him, think that his dreams are the result of a trauma suffered as a result of the death of his biological father just a year ago.
At his apartment in the city of New York, a group of people from an alleged psychiatric unit offered to help Jake over his trauma; Jake, however, recognizes them in his visions as monsters wearing human skin so they run away from them. Jake goes to an abandoned house that he knows of his visions and there he discovers a high-tech portal through which he travels to a post-apocalyptic world called “Middle World.”
In the Middle World, Jake meets with the last gunman, Roland Deschain (Idris Elba), who still appeared in visions. Roland follows Walter Padick (Matthew McConaughey), the black man who also appeared in his dreams in a desert, seeking to kill him for revenge for the murder of his father, Steven. He explains that Walter captured children with special psychic abilities and tries to use their powers to destroy the Dark Tower, a fabulous structure that is located in the center of the universe and which will allow monsters in the dark to invade and destroy reality.