Princess Peach Toadstool has ruled over the Mushroom Kingdom for many years, keeping a calm and kind demeanor as she juggles her monarchly duties with repeated abductions and appearances in sports games. She is the sweetheart of the Mario universe, a pretty pink princess often associated with cakes and hearts and other extremely saccharine things. But is that sweetness just a candy coating produced by Peach to hide whatever disgusting flavor lies underneath? I believe so. Why? Because she is an authority figure who is keeping a secret.
In Super Mario RPG, Mario has access to Toadstool's private chamber inside of the Mushroom Kingdom's castle. There is not much to see or do in this room, but thorough searching will yield a mysterious item hidden behind the fireplace. This item is so mysterious that even its name gives no clues: Toadstool's ???.
The first time you're likely to visit this room is during the initial visit to the Mushroom Kingdom, as it contains the castle's save point. Upon discovering the hidden item, before you are able to tell what it is, Toadstool's grandmother rushes up to you and offers you a Mushroom if you mind your own business. You have no choice but to leave the mystery item alone and take the bribe. Later on, you can go back and try to get the item again after the Princess joins your party, but you will get no closer to the truth on the second try. After finding the ???, Peach will immediately scold you for not respecting her personal property, and the item can no longer be found for the rest of the game.
Before getting started with my theories, I feel I need to get my singular overlying idea down first: whatever it is that Toadstool is hiding, it is something terrible.
The reason why I probably didn't think much about the item for a long time was because I was a young and naive child when I first discovered it. As I grew older, I became wiser to the evils of the world. I became increasingly suspicious of Toadstool and her secret item. If it's something she feels she can't even tell the mustached hero whom she seemingly trusts with her life, it's got to be at least something incredibly shameful, if not downright evil. The fact that she employs her grandmother to bribe you out of studying the object further doesn't really help her case either. Besides, behind fireplaces are where people tend to hide things of a more sinister nature.
??? = secret stash of adult items. The possibility that the nook behind the fireplace is merely where Peach keeps her collection of, ahem, adult items, is one that I will not rule out, even though I personally believe it is the least likely to be true because it is the least "evil". But there is actually a solid clue that points to this theory being true: the secret item's name in the Japanese version of the game is Toadstool's XXX.
Why she would hide such items in this manner is pretty self-explanatory, as no one keeps their unmentionables out in the open for everyone to see. But in Peach's case, it's also about keeping up appearances. Things of an adult nature would be something she would want to try and keep secret from the people who believe she is a pure, innocent soul. Additionally, she would most certainly want to keep it from Mario to keep leading the poor guy along, as if the occasional peck on the cheek is all it takes to satisfy her.
She not only hides these bombs to keep her enemies guessing, but also because she is fearful of tarnishing her reputation as a sweet girl. Peach does not want anyone to know that she is in any way violent, or entertains the idea of nuking Sarasaland every time she has a squabble with Daisy. It would rock everyone's world to realize that the Princess is ten times as dangerous as any Koopa invasion could ever be.
??? = shoe box of memories. Many people keep boxes of memorabilia of the people they've known and the places they've been hidden away from the rest of the world to pull out whenever they want to reminisce about special times in their lives. That doesn't sound so bad until you think about where Peach has spent the majority of her lifetime: in the clutches of villains, namely Bowser. Perhaps there is a reason why the Princess keeps letting herself be taken away by the evil Koopa King, and the memories are all kept stashed away for no one else to see.
As many times as they are attacked, why doesn't the Mushroom Kingdom have an army to combat the Koopas? Because it is all a front. Bowser has expressed love for the Princess many times in the past, and through the way she refuses to do anything to stop him, it's pretty apparent she doesn't really mind having the company of the giant turtle. One could argue that she once left herself defenseless for the opportunity to entice Mario into visits, as he was not originally from her world (being a New York City native) and only made appearances when she needed saving. But now that he resides in the Mushroom Kingdom permanently, there is really no other excuse for her behavior.
The reasons for keeping such mementos from Mario makes perfect sense. If Mario were to find pictures of Bowser and Peach having fun together or love letters that reveal his kidnappings to be planned romantic excursions, not only would it completely break his heart, but it would expose her as a hussy who sleeps with the enemy and leads on the hero just for show. Any leader would want to avoid such a scandal like the plague.
For years, it's been theorized that the reason why Peach gets stolen away so often is because she enjoys it. If only there were more solid evidence, Toadstool's ??? could be the missing link to cement the theory as fact.
Has anyone ever noticed that there is no trace of the King of the Mushroom Kingdom anywhere in any of the Mario series? Peach is always backed up by advisors like the Chancellor or Toadsworth, but never her father. Some may believe she was simply adopted by the Toad people, but there is a King Toadstool. The only place that he's ever actually been seen is in the old Nintendo Comics System comics. There, he appeared to be half Toad, half human, and somewhat scatterbrained.
The most apparent reason why Peach would have to keep such a nasty little secret is, of course, control. Perhaps she felt her father was not up to the task of being a leader because of his simple mind, or she simply wanted to take over before her time to quickly implement her own laws and ideals "for the good of the people". Since getting her father out of her way, she has used poor Toads as living shields and throws her kingdom in chaos each time she goes missing.
However, there is another side to this theory: shame. Outwardly, Peach appears to be the only pure human in a land full of mushroomheads. But the truth may be that she is a mutt, the product of a man who was born of a love between a Toad woman and a human male. Peach is a woman who is trying to hide all traces of her mixed heritage. She is ashamed that she is not a full-blood, as a monarch should be. What better way to deny the past than to hide the proof away, proclaim him deceased, and use his power to feel more in control of her life after feeling out of control of who she really is?
Of course, the list of things that Toadstool's ??? could possibly be is one that stretches as far as the imagination. There are some people who, upon reading this, will agree and add other devious ideas to the list. Then there are some who will suggest that this secret item is nothing to be concerned about because Peach is a kind princess who could not possibly be up to no good. But just think about this before you yourself delve into this mystery: a leader who has something to hide is a leader who cannot be trusted.