Despite years of practice in the art of not freaking out, Night Mist found himself starting to panic. In less than an hour Princess Celestia would be dead. That wasn't enough time. His investigation had only just begun, and he had absolutely no idea what was causing Princess Celestia's sickness, let alone who had caused it. He didn't even have a suspect. Twilight Sparkle, Frazzle Spark, and Sharp Wing were all talking at once, asking him for answers he didn't have, begging for even the smallest crumb of hope. It was a bitter joke that his first failure on a case had stakes as high as this. Of course it hadn't been a missing pet or prized possession being stolen as his first failure. That would have been too easy to cope with. Those scenarios would have been embarrassing, but still bearable.

The words of the three ponies before him were drowned out by a sudden surge of thought, an intensity that sparked a battle within his own mind. He had not failed. Princess Celestia had not yet stopped breathing. The mystery could still be solved in time. The defeated part of his psyche resisted this notion. A mystery such as this could not be solved in less than an hour. The stubborn half of his mind responded by escalating in volume. There wasn't any time to waste. He needed to find the pattern. The details flew by in his mind's eye. The letter, the potions, the slide show, the stake-out. The potion only worked at night. But maybe the position of the sun and moon had nothing to do with it. Princess Celestia could change that easily after all. Something changed when Princess Celestia went to sleep.

A new thought came, a path of possibility. A theory formed in Night Mist's mind. It would be cruel to share it and have it turn out to be wrong, but he couldn't afford not to try. He could have it tested first, there was time for that. Twilight Sparkle would have to be the tester. Despite everything, Night Mist started to grin as a plan formed in his head. Not only could she test his theory, she could help expose the mastermind of the plot at the same time.

"I have an idea, but I'll need your help," he said to Twilight Sparkle.

"What is it? Spit it out!" Twilight Sparkle demanded.

"Take me to Princess Celestia, I'll explain as we go. Time is of the essence."

Within minutes the four ponies arrived in the throne room. Princess Celestia, it seemed, wanted to spend her final moments on her throne. Hundreds of ponies filled the throne room. Servants, wizards, guards, Twilight Sparkle's friends, Princess Luna, all were gathered to watch the end of their beloved princess, and in Luna's case, sister. Light shone through the giant windows of stained glass, a beauty that was in sharp contrast with the solemn atmosphere that hung over the crowd. Princess Celestia sat upright with effort, trying to be brave for all her little ponies, but all of them could see that time was short. Twilight Sparkle's horn glowed a bright pink and then cut off. Then she looked straight at Night Mist and nodded. The theory had been correct. Now came the crucial part.

"If I could have everypony's attention please. I have determined the cause of Princess Celestia's disease," Night Mist called out.

One of the wizards stared at Night Mist.

"And just who the hay are you, a doctor?" the wizard asked dubiously.

"I'm a detective actually, and I know for a fact that Princess Celestia is under a spell."

The wizard's eyes changed from a look of skepticism to pity.

"We've already checked to see if somepony cast a spell on her. That's not the reason."

"You misunderstand, when I said she was under a spell, I meant it literally. There is no spell on Princess Celestia herself, but there is one on her crown!" Night Mist declared as he pointed an accusatory hoof at Princess Celestia's head.

The crowd gave an audible gasp. Night Mist realized the big reveal had been unnecessarily dramatic, but he hoped it would surprise the culprit too. The mastermind would have to be caught off guard for the next part of the plan to work.

The wizard frowned, but turned towards Princess Celestia and lit up his horn anyway. His eyes widened.

"He's right! It's faint, but there is a spell of some sorts on her crown!" he exclaimed.

"Now would be a good time to remove the crown," Night Mist suggested. "That will stop the sickness from progressing."

Princess Celestia unceremoniously swatted the crown off her head with a hoof. The golden and diamond encrusted head ornament fell and bounced once on the marble floor.

"So is she going to live?" asked a servant hopefully.

"She won't die, but she'll be exactly as sick as she is now until you give her another potion," Night Mist informed the servant.

"Then what are we waiting for? Let's make another potion!" called out one of the guards.

"Not yet, first I'm going to identify who cast the spell while we have everyone here," said Twilight Sparkle.

If the crowd was surprised before they were even more shocked by Twilight Sparkle's words.

"You mean to say you already know who did it?" asked Princess Celestia.

"Not yet, but I will in a minute. I'm going to use a little trick called the trace back spell to find out who cursed your crown."

Twilight Sparkle's horn glowed again as she levitated the crown in the air. It slowly moved in a circle as if getting its bearings. Night Mist studied the faces of all the assembled wizards. It would most likely be one of them. The crown stopped circling and started to float towards the wizards. Suddenly Night Mist saw one of them snarl right before a green bolt of energy shot out his horn. Twilight Sparkle ducked and dropped the crown, but it was an unnecessary move. She hadn't been the target. The green blot shot across the room and struck Sharp Wing in the face, causing him to howl as he twitched violently.

"Find me a hostage!" ordered the wizard who had snarled and fired.

It was Rarity who had the misfortune to be standing closest to Sharp Wing. He instantly turned, knocked her down, pinned her on the marble floor with one hoof, drew his swords with his wings and held one near Rarity's throat and the other above his back.

"Any sudden moves or glowing horns and the unicorn loses her head understand?" The wizard snarled at both Sharp Wing and the crowd.

All of them nodded. Night Mist noticed that Sharp Wing's eyes had changed from blue to a sickly green after the spell had hit him. The wizard walked past Twilight Sparkle to be closer to his new puppet and hostage. The Wizard was a brown unicorn with a black mane and goatee wearing a dark blue cape and wizard hat with pictures of stars on them.

"What is the meaning of this, Aurora?" demanded the wizard who had spoken to Night Mist.

Aurora ignored the other wizard.

"Everypony back away from us. I need space to think," he ordered the crowd. They obliged.

"I wasn't expecting it to turn out like this. I've never even heard of a trace back spell," he admitted.

Aurora turned his attention to Twilight Sparkle.

"Just where exactly did you learn that trace back spell? Certainly not magic school or I would have known about it too."

Twilight Sparkle looked as if she wished she was anywhere else.

"I asked you a question," Aurora growled.

"There is no such thing as a trace back spell, at least not that I know of. All I did was move the crown around," Twilight Sparkle confessed.

"Ah, I see. No matter, I can get what I want this way too." Aurora said coldly.

"And just what exactly do you want?" inquired Princess Luna.

"There's a mare being held in this castle's dungeon named Star Bright. I want her released."

"Not a chance," Princess Celestia said with a cough.

"If you don't the unicorn dies."

Rarity whimpered.

"You can't kill her. You need her alive to prevent the other wizards from turning you to ash. I don't have to release Star Bright because you would have to be alive to know for sure I did it. We're at a stalemate," Princess Celestia pointed out.

"That's a problem that's easy to solve, Celestia," Aurora hissed, intentionally dropping the honorific title of princess.

He glanced back at Sharp Wing.

"I want you to hold yourself hostage too," he commanded.

Sharp Wing nodded and adjusted his free sword so that the blade was at his own neck.

"I do believe this gives me the advantage. If you don't free Star Bright the unicorn dies, and if anypony tries to stop me the pegasus dies."

"Fine, will you let both of them go if I free her?" asked Princess Celestia with a sigh.

"Bring her here first and then we'll talk about that."

Princess Celestia tried to say something but she was interrupted by a fit of coughing.

"Do as he says," she commanded the guards when she was done.

Two of the guards glared daggers at Aurora as they departed from the throne room.

"Might I be allowed to stand on my own hooves?" asked Rarity nervously as everyone waited for the guards to return.

"Of course you can my dear," said Aurora with mock sweetness.

Night Mist winced as Aurora cast a mind control spell on Rarity at point blank.

"Stay as you are and don't resist if the pegasus tries to kill you," he decreed once he had finished.