Harry Potter and the Deathly Hallows
Affiliation: Order of the Phoenix
Ministry: Undercover Security Guard for the Muggle Prime Minister, Minister of Magic
Kingsley's name says it all – he's one dignified guy. He's still the strong, able leader that we saw in earlier books, and though we don't see him often, we know he's behind a lot of what goes on in the Order of the Phoenix. He's initially a double agent, still working in the Death Eater-controlled Ministry. But once the Ministry finds out that he's been working for the Order all along, he is forced to go on the run, like so many others. At the end of it all, his abilities and leadership capability is recognized; he's elected temporary Minister of Magic after the Battle of Hogwarts.