Once up a time a white-haired Scotsman compared his life to a battlefield, when everyone else had fallen. And this was true. What was also true was her life was a song, and everyone in it was the melody. The Doctor gets through a rough spot with a little help from her friends and a cosmic musical interlude.
"Maybe every civilization is built on a lie."
When the Master asks for the Doctor's help in terraforming Gallifrey, peaceful fields of red grass aren't the only things that return. For Time Lords, the past is never far behind, bringing with it a terrible secret that threatens to tear apart Team TARDIS forever.
[On Hiatus: Returning in early March]