Nothing has felt right to the Doctor since Rose was sucked into another dimension. Everything’s drab, grey, lifeless, and he’s weighed down by a crushing sense of loss. There’s little point to anything, he’s hollowed out inside, his hearts beat too slowly, and he half expects to crumble into dust.
It’s been a long time since he last felt so devoid of hope.
Then a woman appears in the TARDIS, all red hair and fury, and against his will he’s swept into another adventure. Donna Noble, his candle in the darkness. Without even trying, she restores his will to live.