Douglas Mackinnon is one of Doctor Who’s longest-serving directors. In 2008 he helmed The Sontaran Stratagem/The Poison Sky, in 2013 he defrosted the Ice Warriors for Cold War, and most recently he reunited the Doctor with his wife in the 2015 Christmas Special, The Husbands of River Song. For Peter Capaldi’s first season as the Doctor in 2014, Douglas was assigned a very different type of Doctor Who story. Listen was an episode that took an unexpected trip to the planet of the Time Lords…