5. Rory Williams
The 21st century version of Doctor Who is often defined by its leading lady as much as its Doctor so it's easy to forget that one of the longest running companions of the modern series is Mr Pond himself, the Last Centurion, Rory Williams. Similar to Mickey, Rory began life on the show as Amy's forgotten fiancé back home but after the Doctor tried to patch the two up he joined the TARDIS crew. Unusually for a companion, Rory was only really there for his girlfriend-then-wife rather than for the thrill of the adventure. Despite this, though, he proved himself a highly capable adventurer - and surprisingly proficient at coming back from the dead. Regardless of the danger to himself in the mad world that the Doctor and Amy inhabited, Rory was devoted to his wife and making sure she was safe from harm - as was she to him. When Rory was zapped back in time by a Weeping Angel, Amy left the Doctor behind forever just to be with him. Yeah, that's right. Love's better than the TARDIS, kids.