As Check and the changeling made their way down the hallway, he couldn't help but to notice the bug had taken a unicorn disguise. It made sense really. The ponies were on guard against anything that might appear like a threat. And seeing a pony walking with Luna's chosen detective was far from strange. Or at least he hoped.

Rounding a corner the two stop to see Twilight pacing the halls. "Maybe we should go around." The changeling suggested.

"No. More ponies that know you're on our side the better. And if we tell her what we know…" Check countered as he looked at his companion.

"Tell who what?" Twilight asked, causing the two to look over in shock. "Sorry. I saw the two of you in the hall and…"

"You need somepony to talk to." Check finished.

"How did you know?"

"It's written on your face. I'm guessing it's about the wedding."

"Yes. I think…"

"The bride is a fake."

"The bride is a…" Twilight blinked. "Y…yes… and we need…"

"We need to reveal her and stop her plans before ponies get hurt."

Twilight glared at him for a moment. "How long did you know?"

"Who it is? Probably about the same time as you." He lied. "Regardless, we have a plan… or at least I do. But I'll need you to trust me on this."

Seeing the pin, Twilight nodded. "What do you need me to do?"

"Go get the others. No doubt they'll want to do a rehearsal. Take our friend here with you. Tell them she has news for them." He explained.

"And what if they don't believe me?"

"Tell them I sent her. And that Luna appointed me to find the truth. This unicorn is key to my plan. So keep him safe. I'll get the so-called bride ready." With that said, Check made his way past Twilight. Leaving her with a confused and considered changeling.

In the bride's chambers

Cadence stood at her vanity table as she prepared for the big event. It didn't take long before the door opened revealing a less then amused Check. "Glad we can meet face to face. Or at least, face to mask."

She blinked in shock as she looked at him. "Who are you? And how did you get past the guards?"

"Yeah… something tells me the princess will need to run a few tests on that." He sighed. "If no pony recognized that the babysitter of the princess's top student was acting strange…" He remarked as he gave a knowing smile.

"It doesn't matter. Even if what you say is true. It's your word against mine." She laughed.

"About that… interesting thing about magic. It leaves a kind of… signature. Mind alteration… nasty stuff." He laughed, setting a white bishop on the table.

At those words her eyes grew large. "But… why? How?"

"I simply did what any stallion of peace would. I slipped in and revealed the truth. Now. Before they find the real princess and come to lock you away. How about I offer a deal?"

"And that is?"

"Call off the attack and I'll show you ways to get all the love energy you can ever want."

Cadence licked her lips at the idea. "And if I say no?"

Without a word, Check placed a knight on the table.

Meanwhile
The girls walked down the hall as they kept an eye on their overly eager pink friend. Whatever was coming. She was more than ready for it.

Twilight paced back and forth in her room muttering about how her brother was in danger and how no pony seemed to believe her.

"Relax Twilight. I'm sure everything will be fine." Spike reassured. "I'm willing to bet that somepony believes you."

Twilight's ear twitched as she turned to him in shock. "What? Who? Are you hiding something from me? You know how that annoys me."

Realizing what he said, Spike covered his mouth and shook his head. "Sorry Twilight. I promised I wouldn't tell anypony." He gulped. "I Pinkie Promised."

Hearing about the promise, Twilight sighed and hung her head. "Fine… at least I know I'm not crazy. She is evil… right?"

Spike rubbed the back of his next. "Well… you're the smart one. What other possibilities might there be?"

Twilight thought about it. "Mind control? But that wouldn't explain my brother…" her eyes widened. "Something has replaced her with an imposter."

"So what's the plan?" Spike asked as he jumped to his feet.

"We need to gather evidence. It won't be easy. But I know the real Cadence." She declared. "We'll find what we need."

In the main hall
Luna sat next to her sister looking rather annoyed. "Is something the matter sister?" Celestia asked as she motioned to one of the guards. "You look upset about something."

"Upset? Not at all. I love weddings. Especially in the middle of a national threat." Luna huffed. Taking a deep breath, Luna looked over at her sister. "You know something is wrong."

Celestia let out a deep sigh. "I trust your judgment sister. And if you think this Check will be able to stop this threat. Then so do I." She gave her sister a hopeful smile. "Or is there another reason why you asked for him to be invited?"

Luna blushed and looked away. "You… you know we can't… besides… The law is still new to me… I would like time to study the changes before…"

"I can see if he's interested in sharing after things settle down. That is a possibility… if you were wondering." Celestia teased.

Luna sprinted out of the room shouting. "I will get you for this sister!"

The guards looked at each other for a moment sharing a "Don't get involved" nod, before turning back to their work.

Author's Note

Possible date options are still open. I was thinking between one of the 6 or the sister's. What do you guys think?