>> yevgenia kara-murza: of course i'm terrified. t the same time, you know, i married the guy 13 years ago, and i knew what i was getting into. >> vladimir kara-murza: you know, i think there's nothing better this regime, the putin regime would like us to do than to give up and run away. and we're not going to give him that pleasure. it's our country. >> stahl: even after being poisoned? >> vladimir kara-murza: it's our country. we have to fight for it. >> stahl: he told us this in june. he went back immediately after, even though threats against him had intensified, like this video posted on instagram putting him in the crosshairs of a sniper rifle. he was continuing his opposition work, when just last month-- >> yevgenia kara-murza: all of a sudden, he begins experiencing this very elevated heart rate, his blood pressure drops very low. he begins sweating and he has trouble breathing. >> stahl: his wife thinks her husband was attacked, the same way as before. >> yevgenia kara-murza: the first time, he had been dragged from one hosp