In “The Sunset Limited,” an HBO film directed by Tommy Lee Jones and starring Mr. Jones and Samuel L. Jackson, two men are locked in a room but have almost nothing in common save their time together. In the movie, based on the play by Cormac McCarthy, White, Mr. Jones’s character, is a college professor at the end of the line, a man so pummeled by despair that he attempts to throw himself in front of a train driven by ... Black, a redeemed, religious ex-convict played by Mr. Jackson. White is brought back to Black’s spare New York tenement, and they commence a mortal, desperate debate about the value of life and whether ending it  taking the Sunset Limited  is a valid choice given the amount of misery and alienation that can go hand in hand with everyday existence.

Mr. Jones, Mr. Jackson and Mr. McCarthy  the Pulitzer Prize-winning author of “The Road,” “All the Pretty Horses” and “No Country for Old Men”  spent weeks in rehearsal pulling the play apart, examining each passage for meaning, and then Mr. Jones, who directed “The Three Burials of Melquiades Estrada,” deconstructed what is really one long scene into 52 components, each shot from a distinct perspective. The room’s walls were broken into sections so that pieces could “fly” out of the way, allowing the cameras to roam freely and intimately in the space between and around the two men.

Mr. Jones and Mr. Jackson, along with Mr. McCarthy, who rarely does interviews, agreed to meet at the offices of HBO in New York to talk about the film (which has its premiere on Saturday), the play and working with one another. The three collaborators had lunch and after the dishes were cleared away, David Carr hosted a chat that veered into philosophy and some very big themes but had laughs too, not unlike the movie itself. Excerpts of that conversation follow.

Q. The issues you tackle in “The Sunset Limited” don’t come any bigger. Viewers are literally watching a life-and-death struggle unfold right in front of them, although it is the collision of language that creates the sense of danger, not cars or bullets.