The former Plaid Cymru leader Dafydd Wigley joins Felicity Evans and James Williams at the National Slate Museum in Llanberis to reflect on half a century in frontline politics. Now in the House of Lords, he looks back at the highs and lows of his political career, from the dying days of James Callaghan’s Labour government in 1979, through to the high drama of the devolution referendum of 1997 and beyond. And then there's his connection to a 1930s Chicago gangster and Public Enemy Number 1.