CBS new drama Doubt represents at least two firsts: it's Katherine Heigl's first major series regular role since a short run on State of Affairs; and it's the first network drama that features a trans actor, Laverne Cox, playing a trans character. Doubt is the story of a group of attorneys balancing their personal dramas with their devotion to justice, and the cast and crew couldn't have been more excited to present the show at the Television Critics Association summer tour on Wednesday.

Executive producers Tony Phelan and Joan Rater, a husband and wife team who worked on Grey's Anatomy with Heigl, promise a show that's reflective of 21st century America. "We're going to be telling stories from a broad swath of America," Phelan said, adding that it looks like how New York feels, with various cultures smashing against one another.

The pair in real life has a transgender son and an adopted child from China, and said Doubt tells a new kind of story — coming at a time in which the institutions that are supposed to defend the most vulnerable people don't seem to be doing that great a job.

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Heigl plays Sadie Ellis, a whip-smart attorney at a boutique firm who's hiding her growing attraction to her client Billy Brennan (Steven Pasquale), who's accused of murdering his girlfriend 24 years ago. As Sadie becomes involved with her client, she puts her career and happiness at risk — giving her even more incentive to get him off despite her own doubts in his innocence.

"She's trying to separate herself emotionally," Heigl said, "but struggling with it. We're tying to keep it relatable and human."

This iteration of Doubt reflects a change from the original script: the first version was retooled to make changes to Sadie and Billy's relationship, and Heigl was brought on board. "We got to see parts of the story that weren't working," Rater said. "We got to learn."

Working on other cases at the practice is Cameron Wirth (Cox) a transgender Ivy League graduate; Tiffany Simon (Dreama Walker), a second-year associate learning the ropes; and Nick (Kobi Libii) who earned his degree in prison. Television veteran Elliott Gould plays Isaiah Roth, the team's sage mentor.

"This is a new chemistry," said Gould. "Potentially the chemistry is rather fertile. This is about life, liberty and the pursuit of truth."

Doubt will debut during the 2016-17 season on CBS.