In late February, 31 men, mostly from the Shiite Hazara minority, were kidnapped in Afghanistan, and remain held hostage. This week, five Hazara men were beheaded in the remote eastern district of Malestan, and 36 civilians were killed and 125 wounded in a suicide bombing outside a bank in the city of Jalalabad. These attacks have shaken an Afghan population hardened by decades of war, not just because of their brutality, but because of the whispered name some believe to be behind them: the Islamic State of Khorasan. But how real is the threat from this new group?