Frontline — Episode 1: Mosul/Inside Yemen

You are watching the episode Mosul/Inside Yemen The battle to drive ISIS out of Iraq’s second-largest city was brutal and grueling. Shot over the course of the nine-month battle, “Mosul” follows one Iraqi special forces unit as they lead the fight. Also in this two-part hour: “Inside Yemen” offers a rare, up-close look at the country that’s home to what the United Nations recently called the world’s largest humanitarian crisis.