CBS debuted new legal drama “Doubt” Wednesday (Feb. 15), boasting an all-star cast headlined by “Grey’s Anatomy” Emmy winner Katherine Heigl, “Psych” and “West Wing” star Dule Hill and Laverne Cox of “Orange Is the New Black.”

The show focuses on a New York City law firm made up of a group of crusading lawyers who fervently believe that every person who stands accused of a crime deserves a rigorous defense — a bedrock of the US legal system.

Putting this on display via both two overarching mysteries and several cases of the week in each episode makes for a busy show — through the first three episodes, the show feels a bit overstuffed. Cases of the week that could be really interesting on their own are given fairly short shrift to bring them all to conclusion by episode’s end.

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But the overstuffing does serve one distinct purpose — it affords the show time to move at a snail’s pace regarding the two bigger mysteries at its center. And we like that, and them, enough to recommend it.

First, there’s the murder mystery involving Sadie’s client Dr. Billy Brennan (Steven Pasquale), a handsome pediatric surgeon for whom Sadie has developed romantic feelings. That romance subplot is quite possibly the least interesting thing about “Doubt,” but that’s mostly due to the lack of chemistry between Heigl and Pasquale — the storyline itself is a key element to the show’s premise, and a jumping-off point for the show’s title itself. Sadie, and viewers, are meant to go back and forth on whether Brennan killed his then-girlfriend Amy 24 years prior to the show’s start.

“Doubt” does a nice job with this throughout its early episodes, sprinkling in reveals that alternately make Brennan look guilty and innocent. Three episodes in, we’re definitely leaning more to one side than the other, but — just as in the practice of criminal defense itself — nothing is clear cut, and the show keeps our interest in the murder quite piqued.

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The idea that Sadie might get involved with Brennan, only to find he is guilty after all, is intriguing. We aren’t going to hold our breath that a CBS procedural would go that dark for its lead character, but you never know. It seems like the sort of thing Heigl would go nuts for, looking at the roles and pilots she’s chosen in the past — and we’ll say right now that if “Doubt’s” writers do take the story that way, major props for having the guts to go there.

But what’s even more compelling than the question of Brennan’s guilt is the slow tease of backstory regarding Sadie’s mother, a role in which Judith Light is absolutely stealing the show — and in this cast, that is saying something.

Light’s Carolyn is in jail for killing a state trooper in 1982, when Sadie was just two years old. It’s clear from the jump that there’s more to the story than Sadie even knew — compounded by the fact that Sadie’s boss, Isaiah Roth (Elliott Gould), represented Carolyn and fell completely in love with her. He still considers her an extraordinary woman, which calls a lot of Carolyn’s case in to question — why would Isaiah think so highly of a murderer? (And, of course: What impact does this have on her daughter’s willingness to engage with an accused murderer in turn?)

Even if the central mysteries are moving along at a glacial pace, the show has a fascinating passion for its unanswerable ethical questions and quandaries — we can only hope that the show continues to refine its rhythm, and start honing the focus for the cases of the week so it doesn’t feel quite so frenetic. There’s a lot here, moving at two different speeds, and it’s a little tough to sustain investment with the threat of plot whiplash hanging over your head.

“Doubt” airs Wednesdays at 10 p.m. ET/PT on CBS.

Posted by:Andrea Reiher

TV critic by way of law school, Andrea Reiher enjoys everything from highbrow drama to clever comedy to the best reality TV has to offer. Her TV heroes include CJ Cregg, Spencer Hastings, Diane Lockhart, Juliet O'Hara and Buffy Summers. TV words to live by: "I'm a slayer, ask me how."