Ryan Murphy may have scored a star-studded cast for his HBO adaptation of the Tony-winning play The Normal Heart, but he almost had to do it without Julia Roberts.

Roberts, who took the stage today with the rest of the cast at the Television Critics Association press tour, said her initial hesitations to play Dr. Emma Booker, a doctor with polio who does HIV research, stemmed from what she felt was a lack of understanding about the character. That changed after she saw a documentary on polio. “It unlocked the door to who this woman is to me and where her ferocious pursuit of correctness comes from,” said Roberts. “That’s when Ryan received what he always gets, which is the answer he wants.”

When casting the male characters in the film — many of whom are gay — Murphy said that process involved simply going “after people who we thought would be wonderful and committed in the roles, and that’s what we got.” No thought went to sexuality of the actors themselves. “I don’t think of actors as gay or straight. I think of them as great actors, and I never went after anybody because of their sexuality. I went after what I considered to be the best actors for the part — the one who added the most nuance to it.” Above all, said Murphy, “Really this movie is about love and fighting for love and wanting to be treated equally, and I think that’s an incredibly modern idea. We read about it every day.”

HBO also previewed its half-hour ensemble drama series Looking, which is set in modern-day San Francisco and follows a group of gay friends dealing with their lives and relationships. A critic asked the panel if a show exclusively about gay characters might limit its potential to attract a broad audience.

“There are more straight people as the episodes go on,” said executive producer Andrew Haigh, who also noted the series is very different from the groundbreaking Showtime series Queer As Folk. “It probably is quite gay. Hopefully you quickly forget that they’re gay [and get involved in their stories].” He later added: “I wouldn’t want it to be a show that’s just for gay people. That would be sad for me. There’s a lot more to their lives than that.”

Star Jonathan Groff noted: “All the characters are gay, but that’s not the big issue in their lives. It’s not coming-out stories about people dealing with the fact that they’re gay. They’re dealing with their relationships or with their work or with significant others.”

The Normal Heart debuts in May; Looking premieres Jan. 19.

Here’s the Looking trailer: