The Doctor is dying. There will be no regeneration, no last tricks. This time it's real. He'll be gone soon. The battleground is pitted and scarred, and the Timelord is quiet, dying.
A woman appears. River Song is standing in front of him, radiant. She appears like a valkyrie, those strong women of the north, goddesses of the battlefield. But her purpose is very different. She has not come to collect the Doctor.
River is in Chiswick, and a Donna who knows exactly who the Doctor is stands beside her. She is in the Powell Estate, and girl to whom Bad Wolf Bay means far too much slips across the dimensions. She is on Gallifrey, and a Timelady with an unpronounceable name leaves a TARDIS. She is in a secret base, and a brigadier, a lieutenant, a sergeant and several doctors silently salute. She is in a school, and a girl and her teachers turn to face her. She is in Ealing, and the truest of friends answers the call. All this time, she has been standing, watching the Doctor fade.
Then they are all there. Suddenly, they have always been there. Every child he has ever saved, every life he has ever changed, every friend he has ever made. They are all standing around him, lights in the dark. He can go, they will stay. They throng around him, their faces open, their hearts unafraid. River smiles.
The universe sends its love. The Doctor slips away.