Bryan Cranston spent six months on stage in 2014 giving a tour-de-force performance as President Lyndon B. Johnson in “All the Way.” But adapting the play by Robert Schenkkan for an HBO telepic gave the actor a chance to go even deeper into under the skin of the commander-in-chief who reigned at a turbulent time for the country.

Cranston didn’t hesitate when the offer to adapt “All the Way” came in from HBO because the lesson of the play, about the moral and political courage it took Johnson to push forward on the Civil Rights Act in 1964, was so vital.

“We could now reach millions more and tell this important story by way of HBO,” said Cranston, who won a Tony for the role.

Schenkkan significantly expanded the script from the stage play to incorporate more characters and moments to underscore Johnson’s importance as a political figure. He came into office on the heels of tragedy but his natural political skills and complicated personal history made him the right leader for the moment.

“He changed this country,” Schenkkan said. “We live in Lyndon B. Johnson’s world today. All of the things we’re still arguing about in 2016 started in 2014.” Roach added that the fact Johnson took on civil rights legislation at a time when he was fighting a challenge for the 1964 presidential nomination from the conservative Dixiecrat Democrats made his leadership on the issue all the more significant. “He had so many things working against him at the time,” Roach said.

The movie adaptation opened up greater opportunities for Cranston to use makeup and prosthetics to enhance his appearance as the jowly Texas. On stage, Cranston noted that he did his own makeup.

“We decided to go full-on with the makeup” for the film, Cranston said. On stage and in the film, “I came to enjoy that moment” of getting into makeup while surrounded by pictures of Johnson in his dressing room. While making the film, Cranston made a point of ad-libbing and joking around as LBJ during his downtime on the set in order to remain in character.

Anthony Mackie limns the role of Martin Luther King Jr. in the movie. Mackie said he’d been offered the role of King in the past but hadn’t felt he was ready for the responsibility as an actor in the past. And he was also impressed by Schenkkan’s script.

“It was the first time I read a script that the writer got the essence of who Martin Luther King Jr. was for me,” Mackie said. “That man was not a pushover.”