Some works of fiction live and die on rankings. The characters have their own power hierarchy, but usually you'll find that each character's power level is consistent with their rank.
Then there's the Almighty Janitor.
The Almighty Janitor is that character who is near the bottom of the scale in terms of rank, but is at the top in terms of what he can actually accomplish. Maybe he screwed up in the past, maybe he pissed off the higher-ups and has been paying for it ever since, maybe he's really lazy, undercover, maybe the burden of being a genius took a toll on them or maybe he just likes his job (perhaps more than clinically recommended). Often, his lowly position is the very thing that grants him access to the true levels of power (for one thing, nobody pays much attention to him, so nobody interferes with him). Typically, he'll never go up in rank at all.
