And here we are, the 'final' incarnation of my reimagined, rebooted Doctor Who, portrayed by the wonderful Helen Mirren!
The eleventh Doctor would, after many misadventures, finally retrieve her TARDIS, only to find it terribly damaged. Despite its present uselessness, it is the prized possession of a band of cruel and bloodthirsty space bandits. A battle ensues between the 11th Doctor are the bandits... the Doctor finally triumphs, but horribly wounded. She crawls into her equally moribund TARDIS and dies, before regenerating into the 12th Doctor. After reawakening, the new Doctor realises that the only place she can successfully repair her vehicle/home is by returning to Gallifrey and asking the Time Lords for help. She does so begrudgingly, as the very reason she left her home planet was because of her being staunchly opposed to the Time Lords' delusions of superiority and right to rule over the universe. Nevertheless, she loads the TARDIS into her cobbled-together spaceship and makes for Gallifrey.
Along the way, she settles into her new personality: wise from her many experiences, but also full of wonder and a desire to amaze. 12 is a cross between a wizard and a schoolteacher. She has many companions, young and old, human and alien, throughout her long journey back to Gallifrey.
When she finally arrives, she is astonished to discover that the Time Lords she knew are no more. So much time has passed that they have evolved, so drastically that she does not recognise them. They have become etherial beings of pure energy and information, vastly intelligent but devoid of creativity or emotion. They help her repair the TARDIS, before leaving the planet, in search of other universes to study. Alone on Gallifrey, 12 starts to reconnect with her heritage and makes it her goal to reshape the image of Gallifreyan: no longer a Lord of Time, but just another integral part of it.
Now, why did I put quotation marks around final? Well, a Gallifreyan has 12 regenerations, remember? One more to go...