Dr. Blake arrives from Langley and is put to a test by Martian and Henry. A spooked source threatens to put an operation at risk. Danny's cover is put in play. Martian, overtaken by events, begins to question Sami's motives.

Cast: Michael Fassbender, Richard Gere, Katherine Waterston, Jodie Turner-Smith, Jeffrey Wright, John Magaro, Julia Westcott-Hutton, Evgenios Kakolyris, Violet Verigo, Muneesh Sharma, Marcin Zarzeczny