"Although the essentials of John Fawcett and Graeme Manson's story are not new — a young woman discovers she is part of an international conspiracy/science experiment — "Orphan Black" takes on cloning, which gives it a very high difficulty rating, and around here we give big points for that. Monochromatically urban with requisite glowering skies (it's set in Toronto), "Orphan Black" opens rather ridiculously with Sarah (Tatiana Maslany), an angry young Brit, hanging fretfully around a train station just in time to see her doppelgänger commit suicide. … It's just as ridiculous as it sounds, chockablock with clichés, predictable exposition (two taps of the keyboard and entire histories are revealed) and some fairly whacked-out plot twists. But it doesn't matter because "Orphan Black" isn't so much about plot as it is performance, and as the series continues (BBC America sent out four episodes), the performances are pretty astonishing. Although there are some regrettable Russian/German accents involved, they belong, mercifully, to clones in passing. Between the three main identicals, Maslany shape-shifts with near-miraculous believability, becoming by turns the tough and narcissistic Sarah, the high-strung, multi-tasking mom Alison and the brilliant but sensible Cosima. As an added bonus, the show's take on the assumed identity issue, while still not technically believable, is as convincing as it gets. Sarah is not one of those genetically determined super-agents, so her mistakes with police procedure add a splash of humor, and a scene in which, clearly terrified, she must pursue an armed assailant is nerve-jangling in its realism. It's one thing to learn how to shoot a gun at a target, it's another to face a potential gun fight."