Summer's over: politics is back! This week we return to the mystery inside the enigma that is Brexit to ask where Labour now stands. What is the big divide in the Labour movement: Is it MPs vs leader? Members vs voters? Young vs old? And what could a second referendum achieve anyway? Plus we try to make sense of the fraught fight over the definition of anti-Semitism. With Helen Thompson, Chris Bickerton and Waseem Yaqoob.