The big shocker of Orphan Black's season finale, which aired over the weekend, was not the four-clone dance party, though that was pretty great. It was the fact that there are male clones running around, and we have already met one of them. 

Yes, the big reveal is that Mark, the creepy-looking Prolethean who had been hunting Helena for most of the season, is in fact a clone out of Project Castor, military-raised boy clones. At the end of the episode we see three different versions of this clone: Mark, who is marrying Gracie, the daughter of the evil Prolethean leader; a soldier clone; and a crazed clone, penned into some sort of glass room. 

All of these clones are played by Ari Millen, a.k.a. the boy Tatiana Maslany. (Except for when Tatiana Maslany is playing a boy—but that's another story entirely.) The reactions from recappers to the reveal was a mix of shock and excitement. At Boing Boing, Caroline Siede wrote that the reveal had her "jumping out of my seat with excitement." She continued: "Giving a brilliant actor little to do over the course of entire season just to end the finale with a huge bombshell is the kind of ballsy move that makes me fall in love with Orphan Black all over again." Adam Kepler of the New York Times called the move a "masterstroke from the show’s creators, Graeme Manson and John Fawcett." 

But not all were so pleased.

Though Caroline Framke at the AV Club warmed to the idea, she wrote: "I won’t lie; my immediate reaction at learning that there are male clones was that it was a shame." She later qualified how she grew to like the idea: "Just as much as Dyad and the Proletheans’ treatment of Sarah and her sisters shows how women’s bodies can be claimed and repurposed, Castor could explore how masculinity can be harnessed as a weapon."  Writing at EW Jackson McHenry, explained: "Giving viewers something that has to be shocking (male clones!), left me with only one reaction: 'So... are you going to clean up after this?'" 

An interview with creators John Fawcett and Graeme Manson elsewhere in EW, doesn't entirely make us confident that they will. Fawcett reveals that they had actually planned to kill off Mark in the sixth episode of the season, but "then Ari kept doing these great scenes and we just couldn’t kill him." Orphan Black's plotting has always had a fly-by-the-seat-of-its-pants quality to it, and making Mark a clone seems like another such choice. ("What began as a taut thriller of mistaken identities and unsolved crimes seems poised to keep erecting superstructures without satisfactorily explaining them," Matt Brennan accurately wrote at Slant.) The show, at first, felt ingenious because of its smallness. Maslany is an acting superhero, at this point, but the show could only expand as far as her abilities stretched. With the introduction of another clone, Orphan Black can now grow exponentially, though how much time it will spend with the men of Project Castor remains to be seen. Millen doesn't quite have to capture an audience the way Maslany does, but it would certainly be something of a let down if the male clones weren't engaging in the same way the Maslany clones are. Love for the show's characters has always been a reason to forgive the show some of its flaws, like it's vague villains and sense of place. (What military is this exactly?) 

As the Orphan Black world expands it needs to make sure it's new characters are as strong as its old ones.  We need more Felixs, Helenas, and Alisons, and fewer Pauls and Mrs. Ss. Fawcett and Manson think Millen is up to the task, though the one character we've seen him play, Mark, feels like more of a cipher than a fully formed character. We're reserving judgement.