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.
Martian is a covert CIA agent ordered to abandon his undercover life and return to London Station. When the love he left behind reappears, romance reignites. His career, his real identity and his mission are pitted against his heart; hurling them both into a deadly game of international intrigue and espionage.