Doctor Who: 10 Times The Doctor Lost
6. When Gallifrey Was Invaded By Sontarans
The Doctor and Gallifrey have a complicated relationship. Sure, it's his homeworld and the Gallifreyans are his people, but he's always felt like a bit of an outsider, never truly belonging anywhere or with anyone. Hence the whole, y'know, galavanting throughout space and time in a stolen police box.
This would also explain why, in the Fourth Doctor story The Invasion Of Time, he perhaps didn't show enough care towards the Time Lords (and the planet of Gallifrey as a whole) as he could have done.
This adventure kicks off with the Doctor just showing up on Gallifrey and claiming the Presidency, as you do. From his new position of power, he then aids a race of beings called Vardans in their bid to invade Gallifrey, advising the other Time Lords to surrender and submit to their new alien overlords. If this doesn't sound very Doctor-like, that's because it isn't, and we soon learn that he's actually planning to defeat the Vardans, and helping them invade was all part of his plan to lure them into a trap.
Against all the odds, the Doctor actually manages to pull this off, sending the Vardans back to their homeworld and sealing it in a time loop. However, this victory is short-lived when a group of Sontarans appear out of nowhere and take Gallifrey for themselves, killing Nesbin and generally being much, much worse than the Vardans.
And this hostile takeover stemmed from the Doctor's initial plan, which, while successful, was far too risky, and led to an even worse situation further down the line. Allowing Gallifrey to be invaded, to defeat the invaders? What could go wrong!