New York Times bestselling author, screenwriter and producer Tom Perrotta spoke to students on Wednesday, Nov. 16 about his experiences adapting his books into a film and a television series.

Perrotta talked about the challenges he encounters while adapting his writing for TV or film. Turning a book into a television show or a movie is a “mysterious process,” he said.

The novel becomes less of a blueprint for the TV series, and is more of a “junk shop” to pull characters and ideas from, according to Perrotta, who noted that his 350-page novel, “The Leftovers,” has been converted into 28 hours of story in the television series.

To exemplify one such difference, he read an excerpt from “The Leftovers” in which a character named Holy Wayne is introduced for the first time. In the book, the character is introduced as a white UPS driver whose defining characteristic is his ability to relieve other people of their pain by taking their burdens upon himself.

Perrotta then showed the audience the scene in the television series in which Holy Wayne is introduced. The same character, who is described in the book as a white UPS driver, is portrayed by a black man with a British accent in the TV show. There is also no mention in this introductory scene of the special power Holy Wayne holds, which is so prominent in the book.

Aside from this, in the beginning of the process there were some aspects of the show that Perrotta was disappointed in. When the first season of “The Leftovers” was released, the show was “un-watchably dark,” Perrotta said, as opposed to the novel which strikes a balance between humor and tragedy. However, he quickly learned how to remedy those issues. “I really started to appreciate the show more as we let a little light in,” he said.

Perrotta acknowledged that the world of the screen is vastly different than the world of books, but he is not put off by that difference. In fact, he has relished being part of the writing team for the television series. He has been drawn to TV in recent years because it is collaborative; book writing is a lonely profession, he said.

The most profound difference between writing novels and writing for film and television is that, as a screenwriter, one is limited in describing the characters’ actions, Perrotta said. At a certain point it is up to the actors to figure out how to interpret the writing. Giving a script to the actors is like giving them sheet music and saying, “play the song,” he said.

The lack of space for rich description was never a problem for Perrotta.“I really struggle with pure descriptive writing,” he said, “screenwriting was such a liberation for me.”

Perrotta also elaborated on the differences that exist between writing for film and writing for television. In film, the director is the ultimate authority, Perrotta said. The script is finished by screenwriters before the movie begins shooting, and is often altered by actors or the director during the creative process without consulting the writers. “As a screenwriter, you have to understand that you have a very limited role in this long process,” he said.

In contrast, “TV is a writer’s medium,” according to Perrotta. While the director can change with each episode, the writers remain the show’s constant. “The hierarchy is shifted … the director doesn’t know the show as well as the writers,” Perrotta said.

Perrotta has embraced the differences that come with adapting writing into television or film and is humbled that people are being exposed to his work in this way. “People are able to do things with your material you couldn’t have done yourself … the show takes risks I wouldn’t have dreamed of taking,” he said.

Perrotta is the author of six novels, among them “Election,” “Little Children” and “The Leftovers.” “Little Children” was made into a movie in 2006, the screenplay for which Perrotta was nominated for an Academy Award. “The Leftovers” was adapted into a TV series on HBO in 2014. The third season of “The Leftovers” is set to be released in January.