‘Perry Mason’ gets a gritty new look on HBO, and a (mostly) favorable verdict

“This is not your grandma’s Perry Mason” isn’t much of a marketing pitch. A better description for this sort-of origin story, however, is “Chinatown” meets “Boardwalk Empire,” in a slick, gritty period crime drama that’s good enough to make an argument for watching, if not quite an open-and-shut case.

“You know his name, but not his past,” HBO’s promos say, which assumes, perhaps incorrectly, that people care enough to learn. Yes, the character has been around for decades, but that doesn’t mean anyone was crying out for a “Star Wars”-type prequel.

Originally developed for Robert Downey Jr. (who remains a producer), the eight-episode series stars “The Americans'” Matthew Rhys in the title role, investigating a salacious kidnapping and killing. Yet far from the beacon of square-jawed justice associated with Raymond Burr, this Mason is a boozing, foul-mouthed, divorced scrounger, one who has World War I flashbacks and few compunctions about bending the rules.

Best of all, it’s 1931 in Los Angeles, where the throes of the Depression interact with the seamy side of Hollywood and corrupt power brokers. Mason regularly works for a veteran attorney (John Lithgow), flanked by an associate (Shea Whigham) with even fewer scruples than he has.

The liberties with Erle Stanley Gardner’s creation don’t end there, as other familiar names with unexpected wrinkles pass through Mason’s orbit, such as legal assistant Della Street (Juliet Rylance) and an African-American beat cop named Paul Drake (Chris Chalk).

It’s a period that we don’t see much of on TV, though HBO, notably, has taken runs at it every few years, including the aforementioned “Boardwalk” and before that “Carnivale,” a series that never fully lived up to its eerie Dust Bowl concept.

Still, the revisionist approach from producers Rolin Jones and Ron Fitzgerald has a hit-miss quality, especially in regard to its subplots. On the plus side, the investigation bring in Drake — grappling with racism even before being drawn into these events — and less successfully, an evangelist (“Orphan Black’s” Tatiana Maslany) who becomes involved as well. Homophobia, and the need to stay closeted, rears its head too.

Beyond the impeccable look, the casting screams prestige, including Stephen Root as the district attorney and smaller roles for Robert Patrick, Lili Taylor, Justin Kirk, and a pair of “Boardwalk” alums in Whigham and Gretchen Mol.

For all that, the narrative and pacing aren’t as tight as they could be, and after a solid start, the last few episodes get bogged down in the courtroom. That’s inevitable, perhaps, but nevertheless doesn’t prove as compelling as the buildup preceding it.

There are some amusing callbacks to the character’s mythos, among them Mason being told that nobody confesses on the witness stand — one of several places where at least some familiarity with the source wouldn’t hurt.

“This one’s really got its hooks in me,” Mason says early on, regarding the grisly nature of the case.

Given its enticing setting and appealing mix of elements, “Perry Mason” doesn’t sink its hooks in as deeply as it might; still, in keeping with the legacy of a lawyer famous for almost never losing, the show clears the bar in terms of earning a favorable verdict.

“Perry Mason” premieres June 21 at 9 p.m. on HBO. Like CNN, HBO is a unit of WarnerMedia.