NEW YORK (CNS) — First shown in March 2020 on Britain's Alibi Channel, the limited-series murder mystery "Miss Scarlet and the Duke" debuts on PBS Sunday, Jan. 17, 8–9 p.m. EST.

It's being presented as part of the network's venerable "Masterpiece" franchise, which commemorates its 50th anniversary this year.

The program will air in the same timeslot throughout its six-week run, concluding Feb. 21. But broadcast times may vary, so viewers should consult their local listings.

Set in 1880s London, at the height of Victorian era, the drama was created by Rachael New and directed by Declan O'Dwyer. Thanks, in good measure, to the winsome synergy of its leads — Kate Phillips as Eliza Scarlet and Stuart Martin as William "The Duke" Wellington — the show grows on viewers as it progresses.

Following the mysterious death of her father, Henry (Kevin Doyle), a private detective, Eliza — instructed in Dad's craft from her youth — takes over his agency. Given the period setting, viewers won't be surprised that the novice sleuth meets with reactions ranging from the skeptical to the dismissive.

William, a detective inspector nicknamed for the vanquisher of Napoleon, becomes both Eliza's chief ally in her quest to establish herself and her dramatic foil. For a variety of reasons, it's only natural that Eliza turns to him for help.

The two have been friends since childhood. Like Eliza, moreover, William was mentored by Henry, himself an ex-police official. (Viewers will infer from the dialogue that Henry did not retire from the force by choice.)

Henry's life, we learn, was blighted by gambling and especially drinking, vices that were only getting worse at the time of his demise. As William puts it in speaking to Eliza, Henry's behavior had been "erratic toward the end. I hadn’t seen him sober for months. Neither had you."

Now, however, Eliza sees the same traits manifesting themselves in William. Fearing they will hinder him from achieving his ambitions, she warns him to "tone down your drinking, gambling and womanizing." She also worries that William is only too happy to take the path of least resistance. As a result, she observes, "you increasingly rest on your laurels."

William, for his part, is equally apt to criticize Eliza. "This is my line of work, not yours," he says when Eliza first seeks an entree into his world. Though he eventually comes to appreciate his trailblazing pal's resourcefulness, he still becomes exasperated when called upon to steer Eliza clear of trouble — or get her out of it.

Violence of various kinds and some gore put the series outside the category of family entertainment. So, too, does a subplot about a closeted same-sex romance. True to its publicly decorous epoch, however, the script is mostly free of offensive language — a handful of mildly off-color expressions aside.

It takes a while for the show to engage its audience. The hot-cold tension that famously characterized the relationship between Ted Danson's Sam Malone and Shelley Long's Diane Chambers on the NBC sitcom "Cheers" is, after all, an overly familiar trope by now.

Still, the enjoyable rapport between Phillips and Martin succeeds in carrying the series until it sharpens its focus. Her charming resilience complements his prejudice-defeating — if begrudging — admiration nicely so that their mutual affection seems entirely believable.

"Downton Abby" fans will be happy to see Doyle. So memorable as the proud and striving Mr. Mosley in that beloved drama, he excels here as the unassuming, likable yet tragic private eye — a source of wise counsel to both Eliza and William.

Despite its dark moments and faltering start, "Miss Scarlet and the Duke" will ultimately gratify viewers. They'll come away not only satisfied with the unraveling of an intriguing mystery but with a sense of justice served as well.