Plenty of TV shows have mythological arcs and Russian nesting doll storytelling: There’s a conspiracy, the heroes uncover a villain only to learn he’s not the top baddie. There’s another, higher-level bad guy yet to be discovered.

Secret societies and diabolical organizations are popular, too, and some shows are devoted to nothing but uncovering such groups’ secrets.

BBC America’s "Orphan Black" (9 p.m. Saturday) contains all of these elements, but that isn’t what makes it a great series. It’s the characters, specifically all the clone characters played by one talented actress: Tatiana Maslany.

Maslany, who received a Golden Globe nomination for her exhausting efforts, plays Sarah Manning, who met a look-alike on a train platform just moments before that woman, Beth Childs, committed suicide. Sarah, a former foster child with a history of trouble, assumed Beth’s identity as a cop and began investigating why there was someone else who looked exactly like her. This led her to meet multiple other look-alikes who turned out to be clones:

n Alison Hendrix, a hilariously perfection-minded, uptight suburban soccer mom with a paranoid streak who bonded with Sarah’s flamboyant foster brother, Felix "Fee" Dawkins (Jordan Gavaris).

n Lesbian research scientist Cosima Niehaus, who fell in love with her monitor, Dr.


Delphine Cormier (Evelyne Brochu), an employee of the Dyad Institute. Delphine reports to Orphan Black lead scientist Dr. Aldous Leekie (Matt Frewer). In season one, Cosima started coughing up blood, a symptom of a problem that also exists in other clones.

n Psychotic Helena, who shares a birth mother with Sarah. Sarah shot Helena at the end of season one.

n Rachel Duncan, an ice-cold, self-aware clone who is also the boss of Sarah’s monitor (Beth’s boyfriend) Paul (Dylan Bruce).

Maslany excels at differentiating each role, sometimes playing more than one character in the same scene through the help of digital effects. She ensures that viewers connect to each clone character on a different level, grounding the series and elevating it above typical sci-fi fare.

But the show’s humor really makes "Orphan Black" entertaining. Whether it’s the in-her-head, slightly flaky theorizing of Cosima or the obsessive-compulsive neuroses of Alison or the out-and-proud antics of Felix, in season one "Orphan Black" proved itself an action-packed good yarn and also a fun ride.

The show’s first season ended with the disappearance of Sarah’s daughter, Kira (Skyler Wexler), and her foster mother, Mrs. S. (Maria Doyle Kennedy).

Season two begins in the same spot with Sarah desperate to get Kira back. Eventually Sarah’s on-the-run escape takes her back into the arms of former lover Cal Morrison (Michiel Huisman).

Written by executive producer Graeme Manson and directed by executive producer John Fawcett, Saturday’s season premiere introduces new adversaries for the clones, including Henrik Johanssen (Peter Outerbridge), leader of a new sect of the Proleatheans, who have a complex relationship with science, religion and the clones.

The season premiere also finds Alison reeling from her culpability in the death of neighbor / adversary Aynsley, who got her scarf caught in a garbage disposal and choked to death at the end of season one. Alison also stars in a community theater musical that appears to be about workers who clean up blood at crime scenes.

Through the first four episodes of the new season, "Orphan Black" maintains the terrific mix introduced in season one. The Proleathean storyline seems a bit far afield at first but eventually becomes more engrossing as it starts to intersect with the show’s primary storylines.

Fans of science-fiction who have been disappointed by the offerings on Syfy are advised to catch up on season one of "Orphan Black" and then stick with the show in its new season.

Channel surfing

n USA renewed reality show "Chrisley Knows Best" for a second season;

n Andrew Garfield will host NBC’s "Saturday Night Live" on May 3 with musical guest Coldplay ... NBC will air the pilot of "The Maya Rudolph Show," an attempt to revive the variety show, at 10 p. m. May 19;

n NBC has moved low-rated "American Dream Builders" to 7 p.m. Sunday with "Dateline" at 8 p.m. effective this weekend;

n FX’s "Fargo" got off to a good ratings start April 15, drawing 2.6 million viewers to its debut telecast and a total of 4.1 million viewers over three telecasts that night;

n Spike TV ordered a 10-episode second season of Adam Carolla’s "To Catch a Contractor" to air this fall;

n Cable’s Ovation will air a six-part documentary on "The Royals" beginning at 5 p.m. next Saturday;

n ABC will bring back its "Great Christmas Light Fight" reality competition for six new episodes this holiday season preceded by one-time special "The Great Halloween Fright Fight" this fall;

n The stars of ABC’s "Nashville," including Hayden Panettiere, Clare Bowen, Sam Palladio, Jonathan Jackson, Chris Carmack and Charles Esten, will perform in ABC’s one-hour music special, "Nashville: On the Record" (10 p.m. Wednesday).