Once upon a time in Hollywood, the legal procedural was a noble film genre. From Gregory Peck in To Kill a Mockingbird to Denzel Washington in Philadelphia, Tom Cruise in A Few Good Men to Paul Newman in The Verdict, many an actor has earned his stripes in a role that had him preening in front of a jury box to deliver closing arguments filled with Sturm und Drang and poignant urgency designed to display the full dramatic arsenal.

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Until, that is, basic cable put old Law & Order episodes on re-run 28 hours a day, negating the public appetite for moviedom’s courtroom thrillers. And as a result, such films largely disappeared from studio lineups in recent years (with one notable exception being Sidney Lumet’s perplexing 2006 dramedy Find Me Guilty, which showcased Vin Diesel as a paunchy, balding, middle-aged mobster defending himself in court).

Once upon a not-too-distant time ago in Hollywood as well, Matthew McConaughey wasn’t just known as a himbo with an easy Texan drawl, a ladykiller smile, and washboard abs who delivered winking performances in low-expectation/high-yield rom-coms such as Fool’s Gold and Failure to Launch. Before a string of flops— U-571, EdTV, Sahara—McConaughey was considered a serious actor in the Paul Newman vein tapped to conjoin matinee-idol dimples with serious acting chops. And that initial notion about McConaughey was largely forged by his breakthrough lead part: as the idealistic lawyer Jake Brigance in the 1996 adaptation of John Grisham’s legal pot-boiler A Time to Kill.

Now, after taking a few years off from Hollywood to procreate and tend to his young family, McConaughey’s back with his first film since 2009’s Ghosts of Girlfriends Past. Yes, you guessed it, a courtroom thriller called The Lincoln Lawyer.

In the film—which is based on a novel of the same name by Michael Connelly and arrived in theaters Friday—McConaughey portrays Mick Haller, a hard-charging, street-smart defense attorney (with a pronounced affection for the amber liquors) who practices law in L.A. out of the cluttered backseat of a ‘70s Lincoln Continental. He becomes counsel for Louis Roulet (Ryan Phillippe), the moneyed scion of an Angeleno real-estate family who’s been accused of a vicious sexual assault. Roulet forswears his innocence while sucking Haller into a vortex of danger and corruption, sexual torture, and serial murder that puts the lawyer’s family, friends, and legal practice directly in harm’s path. Shifting between seven gears of charisma—but also anguish and blotto drunkeness—like a Formula One driver, it’s a finely modulated performance by the Texan actor.

Every celebrity worth their puff piece arrives with a juicy meta-narrative to span his personal and professional lives, and McConaughey is no exception. Critics are describing his turn in The Lincoln Lawyer as a return to form, a kind of dramatic redemption after years in the romantic-comedy wilderness (and the less said about the actor-producer’s stillborn 2008 comedy Surfer, Dude, the better).

Turns out the guy was set on becoming a defense attorney before a college detour led him to film instead of the legal arena. So the Lincoln Lawyer role has a kind of dual resonance when taken into consideration with his Jake Brigance role.

“The idea was to go to law school at the University of Texas,” McConaughey recalled. “But in my junior year, I did the math. I’ll be 28 by the time I’m practicing my craft. What about my twenties?”

He continued, pointing out the commonalities between acting and lawyering: “There’s a lot of natural overlap. The defense attorney more than the prosecutor, he’s the storyteller. I sat in a lot of courtrooms when I was getting ready for this part. And I saw attorneys win and blow cases based on their performances.”

McConaughey is aware that people are viewing The Lincoln Lawyer as a game changer for him, and acknowledges that a certain genre fatigue led him to portray a legal eagle once again. “I’d done enough comedies where I was like: ‘Those are fun. I understand that game. But I want to play a different game.’ So I was conscious to that extent.”

But he doesn’t exactly want to throw his craft in rom-com films under the bus. In fact, to hear McConaughey tell it, keeping things airy and light—“skimming across the top of the waves” as he describes it—can take some real doing.

“In a way, there’s more acting to do in comedies,” McConaughey said. “As far as honesty: Is that how you would really react? How you would handle a situation? With jokes? In a way, there’s more acting to not be yourself in those. If I was going to handle life how I would handle things in a romantic comedy, [the romantic relationship] would be over in 15 minutes.”

Nonetheless, McConaughey knows what he’s up against at the multiplex with Lincoln Lawyer, with the legal thriller a vanishing breed in theaters.

“I’m trying to think, what’s the last one that worked?” he asked. “What even came out? Films that are even kind of like this—it’s hard to pick those out.”

A key insight into what makes McConaughey tick is his longtime motto, which doubles as the name of his production company: J.K. Livin’. It’s short for “just keep livin’”—cribbed from a line, the actor unforgettably uttered in his first substantial movie role as slacker David “Woody” Wooderson in the beloved 1993 stoner dramedy Dazed and Confused: “You just gotta keep livin’, man. L-I-V-I-N.” (It’s especially easy to believe given McConaughey’s well-known extra-curricular exploits like nude bongo drum playing, living in his Airstream trailer, and competing in triathlons with Jake Gyllenhaal.)

“I don’t navigate life with full stop ideals,” said McConaughey. “‘OK, now I’m 40. I should do this or that’—I don’t work from that. Just keep livin’, there’s not a ‘g’ on the end of it because, as we say, life’s a verb.”

“This is just another chapter in the same book of my career. It’s a natural evolution. Will I do comedies again? I sure hope so. Just right now, this is what’s turning me on. I’m just glad I’ve got people responding, saying, ‘Hey, really like seeing ya in that role.’ Good, ‘cause I sure did enjoy it!”

Chris Lee is a senior entertainment writer for Newsweek/The Daily Beast. He previously worked as an entertainment and culture reporter for the Los Angeles Times. His work has also appeared in Vibe, Premiere and Details magazines and has been plagiarized in The Sunday Tribune of Ireland and The Trinidad Guardian.