Hamza and Brian visit Tahir Alam, the alleged mastermind of a plot to ‘Islamize’ Birmingham’s schools.

Ira Glass talks with Robert Costa of The Washington Post about President Trump's promise that Mexico would build the wall.Then Brian Reed investigates a wall that may or may not exist. Brian is our senior producer and host of our podcast series S-Town.

Brian Reed continues his story about the town of Homer, Alaska. He talked to all sorts of people involved in the debate over whether the town should welcome immigrants.