The Life and Lies of Albus Percival Wulfric Brian Dumbledore

be known, so he waits for an opportunity to let Harry know in an inconspicuous way. And just such an opportunity presents itself when Harry and Hermione land themselves in detention!
At this point, something has been killing the unicorns in the Forbidden Forest, and Dumbledore has likely put two and two together and realized it’s Voldemort. Dumbledore sees this as a good opportunity to tip Harry off about the Stone and about the fact that Voldemort is after it. He decides that the detention will take place in the Forbidden Forest.
This is the only plausible explanation for that detention. Even by Hogwarts’s very lax standards, sending four first years into the Forest at night, when they realistically are no help in finding a dead unicorn, is absurd. It’s certainly not McGonagall’s style, and until Dolores Umbridge comes along, the detentions mostly consist of cleaning and other sensible things. The idea for this detention was almost certainly part of Dumbledore’s plan.
One thing that always struck me as odd was that Firenze knew about the Stone. He is the one who helps lead Harry to the conclusion that Voldemort is trying to steal the Sorcerer’s Stone—after explaining what unicorn blood does, he asks Harry, “Mr. Potter, do you know what is hidden in the school at this very moment?” (SS259) Why would Firenze, a centaur who has nothing to do with anything, know about it? Unless the meaning of “Mars is bright tonight” is “There’s a Sorcerer’s Stone hidden at Hogwarts,” there’s no way for Firenze to know about it. . . unless Dumbledore tipped him off. After Dumbledore planned Harry’s excursion into the Forest, he likely sought out the most approachable centaur and instructed Firenze to watch over Harry and tell him about the Stone and Voldemort at an opportune moment.6
Did Dumbledore plan the meeting in the forest between Harry and Quirrell? I’m leaning towards no, because that would needlessly endanger Harry and the other students. Also, Dumbledore doesn’t really have a way of knowing which nights Quirrell goes to drink the unicorn blood. I think we can give Quirrell enough benefit of the doubt to not drink it on a regular schedule. That run-in was a coincidence, but luckily Firenze was watching over Harry, and no harm was done.
Another subtle clue of Dumbledore’s involvement is that he returns the Invisibility Cloak to Harry that night. Why that night, of all of them? Because Dumbledore counted on Harry now knowing what’s going on and equipped him with the Cloak to go after Quirrell.
Now the only thing for Dumbledore to do is to leave and allow events to unfold. Perhaps Quirrell just happened to choose the last day of Harry’s exams to send Dumbledore away, or perhaps Dumbledore waited until the exams were done so as not to interfere with Harry’s education. Either way, about a week after the incursion into the Forest, Dumbledore gets an urgent owl from the Ministry and “leaves,” allowing Quirrell and the Trio to go after the Stone.
Here we get evidence that Dumbledore’s staff is not privy to the plan for the Trio to go through the trapdoor. When Harry reveals he knows about the Stone, “Whatever Professor McGonagall had expected, it wasn't that. The books she was carrying tumbled out of her arms, but she didn't pick them up.” (SS267) So unless McGonagall is just having a laugh and doing a bit of acting (there is a theory that she carries a stack of books around just so she can keep dropping them for dramatic effect), this means that the staff was not aware that the protections they were creating were custom-made for the Trio. This is very much Dumbledore’s style; he will employ a similar lack of disclosure in Order of the Phoenix, when he assigns tasks to his allies.
Did Dumbledore actually go to London? Perhaps, but if he did, he certainly got back much sooner than he leads us to believe. Hermione tells Harry, “I brought Ron around—that took a while—and we were dashing up to the owlery to contact Dumbledore when we met him in the entrance hall—he already knew—he just said, ‘Harry’s gone after him, hasn’t he?’ and hurtled off to the third floor.” (SS302)
Dumbledore is all about timing. He wanted to give Harry some time to face off against Quirrell but would then dash in to end things. So he carefully planned it. After the potions puzzle, Harry would go to fight Quirrell, while Ron and Hermione would return. Dumbledore watched them go, waited for Ron and Hermione to emerge, which would be his cue to go after Harry—that would give Harry enough time.
What Dumbledore hadn’t counted on was Ron getting injured and Hermione having to take time to revive him. He was frantic by the time Ron and Hermione got to him: he knew that they should have emerged sooner. That’s why Dumbledore “feared [he] might be too late.” (SS297) He also must have received quite a shock when he arrived and saw the Sorcerer’s Stone was no longer in the mirror! That was his first sign that he was dealing with an extraordinary boy.
Upon reflection, Harry was quite right—Dumbledore did orchestrate much of what happened that year at Hogwarts. All the protections surrounding the Stone were meticulously planned by Dumbledore for the Trio. Some parts of the plan went wrong—like Harry getting the Stone out of the mirror and Ron getting injured. And there were quite a few coincidences—Quirrell trying to steal the Stone just after it was taken, Harry meeting Quirrell in the Forest, and Harry finding out about Nicolas Flamel.
But on the whole, this plan turned out all right. Throughout the year, no one was really the wiser about Dumbledore’s scheming, and Harry now has his first victory over Voldemort. To be sure, this all seems like a lot of effort for Dumbledore. But Dumbledore has the luxury of having time to set up such elaborate plots, because the wizarding world is at peace. Now that it’s all resolved,