Complex sentence: The screenplay was adapted by Kate Lanier from the book "I, Tina" written by Tina Turner and Kurt Loder and both Ike and Tina Turner assigned rights to Lanier for their lives to be dramatized in the film.
Split into simpler sentences: The screenplay was adapted by Kate Lanier from the book "I, Tina" written by Tina Turner and Kurt Loder. Both Ike and Tina Turner assigned rights to Lanier for their lives to be dramatized in the film.