Spike Lee is making a movie about a scientific pioneer who is building a time machine.
Lee has bought the film rights to physicist Ronald Mallett's memoir, which tells the tale of his lifelong quest to create a workable means to travel through time.
Mallett, 63, became obsessed with the subject as a 10-year-old, following the death of his father.
Lee describes the project as a "fantastic story on many levels and also a father and son saga of loss and love".