James froze, his frustration transforming instantly into shock and curiosity.
That couldn't be right. Hogwarts was the most magical place in the British wizarding world. The walls themselves should be saturated with centuries of ambient magic. The detection spell hitting the wall should have lit up like a Christmas tree, showing layer upon layer of protective enchantments, strengthening charms, and any other magic imbued in them.
But it showed nothing. The wall registered as completely mundane, as if he'd cast the spell at his bathroom wall at home.
Actually, his room at home would probably show more magic. He'd cast dozens of spells on those walls over the summer. The color-changing charms alone should have left traces. His mother had really enjoyed the free repainting, he remembered with a small smile.
But the thought pulled him back to the present mystery. Hogwarts walls shouldn't show up as non-magical. They should be leaking magic, glowing with it. Yet the detection spells read them as completely mundane.
Which meant the spells on the walls were somehow prevented from showing up on detection spells.
James felt the thrill of discovery rush through him. He hadn't wasted his time after all. He'd found something important. The suits of armor weren't special in their immunity to detection spells. The entire castle was.
But he needed to verify. He needed to test more locations, compare different areas, see if the effect was consistent throughout Hogwarts.
James began walking again, this time with purpose. He fired detection spells at every wall he passed, at doors and windows and floors and ceilings. If someone had been able to see him, they would have thought him an insane maniac, obsessively casting the same spell at everything in sight.
Several awake portraits noticed the magical flares and called out confused questions. "Who's there? Show yourself! What's all this spell-casting about? How rude!"
James ignored them and continued his systematic testing. Walls, floors, ceilings, doorframes, alcoves. Every structural element of the castle he could reach.
He was self-aware enough to recognize the irony. He'd decided to be careful, to stay hidden, and to avoid drawing attention. But as soon as an interesting enough mystery and puzzle appeared, he'd completely disregarded all his previous precautions.
But that definitely didn't stop him from pursuing this path. The discovery was too interesting for him to resist.
The frustration he'd felt earlier about the suits of armor had completely evaporated, replaced by the excitement of finding a genuine mystery. Now he had somewhere to begin. He knew this phenomenon wasn't unique to the armor or to the Rowena Ravenclaw statue in the common room.
James believed the statue and the suits of armor were probably as old as Hogwarts itself, probably created by the Founders. They showed the same resilience to detection spells because they were made using magic so old or different that modern detection charms couldn't recognize it.
As he explored, James found two classrooms with locking charms and secrecy spells on the doors. The magic showed up clearly on his detection spells, modern enchantments that were well within the scope of what NEWT-level spells could detect. The rooms probably belonged to older students who wanted private spaces to practice or socialize away from teachers.
On unlocking one room was filled with both magical and Muggle board games and quite a few comfortable seating options. A club room of some kind, perhaps.
But the structural elements of Hogwarts itself remained stubbornly invisible to magical detection.
A thought struck James, and he changed direction abruptly. He needed to test his hypothesis in a location he knew had powerful modern magic: the third-floor corridor.
He made his way through the castle more quickly now, no longer stopping to test every surface. He climbed staircases and navigated corridors with growing confidence in his ability to remain undetected.
When he reached the third-floor corridor, James paused to ensure no one was around. Apart from the professors, Voldemort himself was monitoring this area through Quirrell. Not to mention the various reckless and overly curious students who would no doubt be tempted to brave the dangers of the forbidden corridor despite Dumbledore's warnings.
James approached the large oak door carefully and cast his detection spells.
Finally, results.
The door lit up with magical signatures. Locking charms, layers of them. Strengthening enchantments on the wood itself. And several advanced charms that registered as dangerous, likely referencing Fluffy, the three-headed dog guarding the trapdoor beyond.
Modern magic. Added recently. All of it, clearly visible to detection spells.
But when James cast the same spells on the walls surrounding the door, on the floor and ceiling? Nothing. Just like everywhere else in the castle.
He smiled, satisfied that his hypothesis was holding up. Time for the ultimate test.
James made his way up through the castle, taking moving staircases that carried him higher and higher. Four floors up from the third-floor corridor, he reached the seventh floor and turned into the left-hand corridor.
The Room of Requirement was located here, with its hidden entrance opposite the tapestry depicting Barnabas the Barmy's attempt to teach trolls ballet. James had memorized its location from the books, though he'd never actually seen it appear.
He stood in front of the blank wall where the door should manifest and resisted the urge to pace three times while thinking of what he needed. Instead, he raised his wand and began casting detection spells directly at the wall.
No reaction. Nothing. The wall showed up as completely mundane, utterly non-magical.
James's smile widened. Perfect. This was the most magical room in Hogwarts that he was aware of, a space that could transform itself into literally anything the user required. If any location should have blazed with magical signatures, it was this one.
Yet the detection spells showed nothing. The wall could have been in a Muggle building for all the magic the spells detected.
His hypothesis was confirmed. Whatever magic the Founders had used to build Hogwarts, it was so fundamental, so deeply woven into the castle itself, that modern detection spells couldn't recognize it.
It was like trying to detect water while swimming in the ocean. The magic wasn't hidden; it was simply operating on a level that NEWT-level detection charms weren't designed to perceive.