A very bad man

The Master actually has a lot in common with his nemesis, the Doctor. They both have pretentious, attention-seeking names, for example. Both graduated from the Time Lord Academy at around the same time, and both decided to steal TARDISes and whimsically wander the universe.

Of course, the big difference is that the Doctor is a fun-seeking galactic hobo, while the Master’s travels are motivated by his desire for complete domination of everything and everyone.

The Master also had the sense to actually steal a good TARDIS. His still has a functioning chameleon device, which means it can change its appearance (rather than look like, say, a police box all the time).

Indeed, the Master was so annoyed by the Doctor’s TARDIS that he called it an "overweight, underpowered museum piece... might as well try to fly a second-hand gas stove."

Holmes and Moriarty

The love-hate relationship between the Doctor and Master really began when the evil Time Lord appeared on Earth while the Third Doctor was stranded there.

He started as he meant to go on: stepping out of his TARDIS, introducing himself as the Master and hypnotising his first minion. He wasn’t exactly Earth’s biggest fan ("One day I will destroy this miserable planet!"), but he had a lot of fun during his stay here, teaming up with the Daleks, using black magic to summon pagan gods, and assuming unsubtle aliases like 'Colonel Masters' and 'the Reverend Mr Magister'.

Despite constantly battling, the Doctor and the Master were grudgingly fond of each other. After all, they were both renegade Time Lords and they admired each other’s genius, and their skirmishes unfolded like an endless game. But it couldn't last, of course, and things got really nasty...

Bad face days

Unfortunately for the Master, he was actually in the last period of his last life (well you get through a lot of regenerations when you’re a galaxy-hopping maniac). So, by the time the Fourth Doctor crossed paths with his old friend/mortal enemy, the Master wasn’t quite as suave and playful as he was on Earth.

No, by this time he was a rotting, corpse-like creature in a hoodie, skulking in shadows and frankly in no mood for jokes. To grab himself some more regenerations, he decided to go back to Gallifrey and attempt to channel the power of the Eye of Harmony (a 'tamed' black hole which fuels Time Lord society).

Luckily, the Doctor messed up his plans – but the Master did later manage to take over someone’s body and become dapper once more.