Covert CIA agent Martian is called back to London Station. Series premiere.

A spooked source threatens to put an operation at risk.

Martian finds a needle in a haystack and confronts Sami about London.

Henry and Martian run diplomatic interference. Danny walks a tightrope.

Henry sends Owen to Minsk in a hunt for clues. Martian sets a rat trap.

Martian scrambles to unravel Cossack’s game. Osman plays his hand.