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

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

A spooked source threatens to put an operation at risk.

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

Martian's approach doesn't go to plan. Sami makes a startling confession.

Martian buys time with a bluff to Langley. Danny crosses the Rubicon.

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

Covert CIA agent Martian is called back to London Station.

Bosko is briefed on Valhalla. Martian, Henry and Naomi strategize a play.

Bosko shares a grim truth. Martian makes a devil's bargain.