There's a crisis underway! The AlienInvasion is imminent, there's a [[AttackOfThe50FootWhatever 50 foot tall monster]] ready to attack [[ThrowAwayCountry Tuvalu]], a huge cache of nuclear missiles may be [[ANuclearError launched needlessly]], a [[ThePlague humanity-destroying virus]] is about to be released on the unsuspecting public, and [[ArsonMurderAndJaywalking the President's daughter has strep throat]]!! No matter, there's a huge team of scientists working on it. The entire world's best efforts are focused on the problem, and -- wait, that one guy at the hot dog stand in Des Moines has the solution! Never mind how grossly unqualified he is, how totally unconnected he is to the situation, he knows exactly what's going on, [[CassandraTruth if only he could get them to believe him]]. It seems in a big world full of know nothing experts, he is The One Guy With A Brain. In a WhatCouldPossiblyGoWrong situation, he's the only one who sees it besides the audience.
Why isn't this guy in charge of the crisis? Well, maybe he's a CowboyCop who is held back for insubordination. Maybe the ObstructiveBureaucrat won't promote him because he never technically got his degree. Maybe he made a career-limiting mistake in the past, or TheRival made it look that way. Maybe he's a child-prodigy, but is dismissed for being JustAKid. But it could be that our hero just likes their current job and has turned down better positions, or is an enthusiast on the subject who doesn't want to mix their passion with work. In any case, the real reasons are that we like to see an underdog win, and we want a protagonist we can identify with.
In a long running show, it's tempting to make a character into one of these for a day, especially an EnsembleDarkhorse or a CreatorsPet. When this happens, expect everyone else to [[ContrivedStupidityTropes suddenly drop 50 IQ points]] while our hero saves the day.
Compare IgnoredExpert, TheCassandra, OnlySaneMan. Related to TheOnlyOne, and may overlap with TheMainCharactersDoEverything. See also TooDumbToFool, for when the obvious solution is too obvious to be noticed.
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