Audiences were stunned when Clara led the First Doctor and Susan to his TARDIS on Gallifrey. Fractured across his time, saving him from the Great Intelligence, she became one of the most important companions in the history of the show. But despite that surprise appearance in series seven's The Name Of The Doctor, it wasn't until Listen where we finally saw the first meeting between the Doctor and his future companion. We'd glimpsed the Master's childhood before but now we saw the Doctor as a boy; weeping and huddled in a barn (more on that later), possibly orphaned and isolated from the other boys around him. It was a dramatic revelation not just because Clara grabbed his arm from under the bed, becoming the very nightmare the Doctor was seeking, but also because she was the one to sooth his distress and presumably allow him to continue on the path before him. While Clara being the nightmare ruined the impact of earlier scenes, her meeting with the young by on Gallifrey only cemented her connection to the Doctor . Just as long as you don't question how the TARDIS made it to an early point in the planet's history when it's supposed to be time locked!