In an interview with Variety, playwright Kramer said the sequel will start "around the end of 'The Normal Heart' in 1984. And it goes [up to] the appearance of the first drugs around 2001. Mark Ruffalo, who we hope will repeat his performance, will have to play Ned at a few times in his life: at the time of 'The Normal Heart'; in the middle where he gets sick; and today."

The role of Ned will remain the main character; however, the role of Tommy Boatwright, played on stage and on screen by Jim Parsons, will be much larger in the sequel. "He becomes a more important character in the sequel," Kramer said, "as he was in my real life." The playwright hopes Parsons will also return for the continuation of the story.

When asked whether Julia Roberts will again play Dr. Emma Brookner, Kramer responded, "I certainly hope so. [Director] Ryan [Murphy] wants to use the same actors as in the first movie, if he can get him. It was a very close company. In the sequel, the part of the doctor is quite dramatic in that her polio returns and she has to go into an iron lung, and she conducts business from the hospital."

Directed by Emmy winner Murphy (“American Horror Story,” “Glee”), Kramer adapted his landmark stage production for the screen. The 9 PM premiere on May 25 was watched by nearly 1 million viewers, with an additional 435,000 viewers tuning in for a second airing at 11:15 PM.

Ratings for "The Normal Heart" placed the film fifth in viewership among the 17 HBO films to have premiered on the network since 2010. Read: A Normal Heart Viewing Party: Two Generations of Gay Men Watch the Past Turn Into the Future on HBO

Academy Award winner Roberts was cast as Dr. Emma Brookner, with Matt Bomer as Felix Turner, Ruffalo as Ned Weeks, Taylor Kitsch as Bruce Niles, and Parsons reprising the role of Tommy Boatwright that he played on Broadway. Tony Award winner Joe Mantello, who portrayed Ned Weeks in the 2011 Broadway premiere of Kramer's play, played Mickey Marcus.

Read: Normal Heart's Jim Parsons on Coming Out and Why Larry Kramer Scared the Hell Out of Him

The cast also featured Jonathan Groff (Spring Awakening), Stephen Spinella (Angels in America), Normal Heart Broadway co-director Joel Grey (Cabaret), Denis O'Hare (Take Me Out), BD Wong (M. Butterfly), Alfred Molina (Red), Corey Stoll (A View from the Bridge) and Finn Wittrock (Death of a Salesman).

Accoding to HBO: "Ruffalo portrays Ned Weeks, who witnesses first-hand a mysterious disease that has begun to claim the lives of many in his gay community and starts to seek answers. Bomer plays Felix Turner, a reporter who becomes Ned’s lover. Kitsch plays Bruce Niles, a closeted investment banker who becomes a prominent AIDS activist. Parsons plays gay activist Tommy Boatwright... Roberts plays physician Dr. Emma Brookner, a survivor of childhood polio who treats several of the earliest victims of HIV-AIDS.

"Molina plays Ned’s older brother, Ben, who is a successful attorney. Mantello plays Mickey Marcus, who is an instrumental member of the Gay Men’s Health Crisis. Groff plays Craig, Bruce’s lover, an early victim of HIV-AIDS. O’Hare portrays Hiram Keebler, Mayor Koch's gay aide. Spinella plays Sanford, one of Dr. Brookner’s first patients. Stoll portrays presidential senior advisor John Bower. Wittrock plays Albert, a male model. Wong portrays Buzzy, a nurse who works with Dr. Brookner."

Executive-produced by Murphy, Jason Blum, Dede Gardner and Dante Di Loreto, "The Normal Heart," according to press notes, "tells the story of the onset of the HIV-AIDS crisis in New York City in the early 1980s, taking an unflinching look at the nation’s sexual politics as gay activists and their allies in the medical community fought to expose the truth about the burgeoning epidemic to a city in denial."

The creative team for the film included production designer Shane Valentino, director of photography Danny Moder, editor Adam Penn, costume designer Daniel Orlandi and composer Cliff Martinez.

Kramer’s play debuted at New York’s Public Theater in 1985. The 2011 Broadway revival garnered five Tony nominations, winning for Best Revival, Best Featured Actor and Best Featured Actress.