From the last episode it looks like Mark was a goner but this week it seems that Sarah might save her brother clone. Here is how Space Channel is describing Orphan Black’s 4th episode:

Mark is taken down in a Prolethean shoot-out and Sarah must step in to help. But as Sarah gathers intel that puts her on the trail of the original Castor DNA, a familiar foe is not far behind. While Helena continues to toil in a faraway military compound, it is ultimately Sarah’s fate that will hang in the balance as she tries to save her sister. Meanwhile, Gracie is cast out from the Prolethean fold, and Alison and Donnie come face-to-face with unhappy drug lord, Jason Kellerman.

“Never Elements of our Defense” airs this Saturday May 9th, 2015 at 6pm ET/10pm PT on Space Channel and BBC America.

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