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Newer Elements of Our Defense
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.
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Other episodes for this season
![The Weight of This Combination](https://image.tmdb.org/t/p/w300/rBHIfdRq3O8pna4qbE7ytTbC1hh.jpg)
![Transitory Sacrifices of Crisis](https://image.tmdb.org/t/p/w300/dXppe0PjUEMmTymratnvVYZuxea.jpg)
![Formalized, Complex, and Costly](https://image.tmdb.org/t/p/w300/y8q1HRMDIgn7p0BrVqdnFdGpCJp.jpg)
![Newer Elements of Our Defense](https://image.tmdb.org/t/p/w300/A0cynlm6dbzXpji3fpzNtW37B48.jpg)
![Scarred by Many Past Frustrations](https://image.tmdb.org/t/p/w300/vV4mOijhBCImrSsWt1LZnIjmJTE.jpg)
![Certain Agony of the Battlefield](https://image.tmdb.org/t/p/w300/nxfv3ovOaAZeZy0bpj8VkOTStHe.jpg)
![Community of Dreadful Fear and Hate](https://image.tmdb.org/t/p/w300/iRsuJ1YOE8e5Acsn6vNwT2jmdmU.jpg)
![Ruthless in Purpose, and Insidious in Method](https://image.tmdb.org/t/p/w300/uAbjyb2XIjgkEniDREY8FCRcFiZ.jpg)
![Insolvent Phantom of Tomorrow](https://image.tmdb.org/t/p/w300/tJUpyt96IqxPqt9htnCICxtqmNz.jpg)
![History Yet to Be Written](https://image.tmdb.org/t/p/w300/b7yBUxegPKpBjSxqI9LyETvvUut.jpg)