Biography
You ever heard the warning "Never meet your heroes"?
There are people we admire, even idolize; people who are everything that we want to be. Even if we meet them only briefly, they have the power to change our lives. These mentors and idols teach us to use our full potential and do great things, and not only do we love them for it, we imagine that nothing could ever tarnish the memory that we hold of them.
Unfortunately, sometimes something does. And nowhere is this more true than in fiction.
When this trope is in play, if you look up to someone, chances are good that they're the scum of the earth. At the least, they’re not what you think they are — or they were, but time has passed and the luster has faded. (This is particularly likely if the audience has just heard about them for the first time). If you're in law enforcement, you'll probably suffer the double blow of seeing their darkest secrets and having to be the one to put them in handcuffs. If your idol was your teacher, you'll find yourself repeating — with bitter irony — some maxim or mantra that you still hold but your mentor has since abandoned.
What makes a pedestal break varies, but it runs anywhere from a good person who abandoned their ideals or switched sides to a monster who was Evil All Along. Most of the time, the idol kept his shining image by hiding or suppressing anything damning, but sometimes the fault was in those who worshiped him and saw an overly idealized image instead of the real person. Or maybe others saw the signs of bad in them, but the one who supported the idol, a friend of theirs, insisted that the idol had a Hidden Heart of Gold that only they could see, only to realize everyone else was right about them all along. Expect them to ask, "Was It All a Lie?" Is also frequently a result of a Deceptive Legacy or Insidious Rumor Mill being revealed to the deceived parties.
Sometimes, the pedestal being broken is already deceased. In most cases, it will be someone the hero(ine) knew personally, allowing for more grief and rage from a sense of personal betrayal. However, it can still occur with iconic figures held up by society whom they did not know on a personal level. There is no space for the deceased to defend or redeem themselves. Thus, the conflict for the living person who has learned harsh truths about their dead idol becomes more of an internal struggle.
This trope disallows real life examples, and with good reason. If you have ever had someone turn on you at least once or realize the person you looked up to and considered a friend is the opposite of what you expected, you'd concur that this trope is Truth in Television. In fact, you'll be surprised that it's more if not just as common in Real Life as it is in fiction. Should real life examples be allowed, there would be a risk of this page crashing because there's just that too much to list.
It doesn't always have to involve celebrities, either. It can also be the last person you'd expect (or want), like your Childhood Friends or your older brother (or sister), even your own parents if you're unlucky enough.
When the mentor or idol is both worthy of admiration but shows demonstrable flaws, that's Warts and All.
Related to Beleaguered Childhood Friend, Fake Ultimate Hero, False Friend and Big Bad Friend. Compare Fallen Hero and Historical Hero Upgrade. Also compare Defiled Forever, My Girl Is Not a Slut, Unpleasant Parent Reveal, and Disappointing Heritage Reveal. Also coincides with Nice Character, Mean Actor since an encounter with such a person can lead to this. Also see Replacement Pedestal, for when a character who is disillusioned with a former role model finds a better one to look up to. Contrast with Evil Mentor, who was Obviously Evil from the beginning. Not to be confused with Broken Base. Also contrast Rebuilt Pedestal, when a formerly Broken Pedestal is forgiven or exonerated. Contrast with Blind Obedience where this usually isn't the case.
Due to the nature of the trope, there will be unmarked spoilers abound. You Have Been Warned!