Nurse Bluebell walked up the corridor and stopped at her office, "Hello Felix, any troubles here tonight?" The moon was due to set any moment as Princess Celestia walked with the nurse. "None at all Nurse. Princess Luna came to visit her earlier and is still inside. It's actually... been rather quiet." He said realizing how long its been since he spoke to the night princess. Celestia raised an eyebrow, "Really? She should be setting the moon about now, that's where I'm headed after this." Felix nodded and opened the door.

Bluebell walked inside and froze when she found the Pegasus mare sitting up right with a startled look painted on her face and gasping in a panic. "OH MY GOODNESS! Quick, we need Doctor Maple in here!" Felix saluted and rushed off to find the doctor. Bluebell rushed to the young mare's side to check her vitals over. "Easy easy!! You're safe here!" Trying to calm the panicked pony down she noticed that a turquoise aura was glittering around the mare's hooves blinking off and on out of control. "What's wrong with her Bluebell?" Celestia asked stunned at what she was witnessing. It's nothing like she's ever seen before. The nurse looked at the princess and had a look of confused concern plastered on, "I don't know Your Highness! It's like her body is in a state of Magical Flux or something."
"What does that mean?"
"Well, it means that it's like she's in a state of shock, but her magic has returned and is affected as well. It seems to be activating and disactivating each time."

Celestia listened to the nurse's comments and started to understand what she meant. There was only ever one other case of this and that was due to an encounter with Discord before he was reformed. But before she could think of how she could help the young mare, the Pegasus began to settle down and the shaking stopped as her muscles calmed to a relaxed state. The nurse sighed in relief as she took out the needle she had just injected into her flank. "There.... That should relax her a bit." Bluebell wiped the needle with a clean cloth and placed it into a sterile bag. "Thankfully that one other case we had many years ago provided the health system with a cure for this condition. She should be fine now that she's woken up once already. The next time she wakes up, she should be on the road to recovery from the dark magic." But when the unicorn mare looked towards the alicorn she saw that she was frozen in place with a look of horror on her face.

"Uh, Your Highness? Are you alright?" She took notice of where her gaze was directed, towards the balcony that had the doors wide open and something dark laying on the floor. "Oh my goodness Princess Luna!" The unicorn rushed over to the blue alicorn's side and crouched low over her motionless body. Checking her eyes with a light spell from her magic, she discovered that she was in the same state that the Pegasus originally was. "Oh no..... don't tell me it's contagious! This is why it's still night time!" Nurse Bluebell shivered at the thought as she rang the bell on the inside of the room with her magic to alert the guards outside, "Guards!" Celestia woke up from her frozen trance of shock. "Luna!" She hurried over to her young sister that looked like she'd been injured somehow and knocked unconscious. The nurse saw the guards come running into the room, "Yes Nurse! We heard yelling."
"Go fetch the doctor, now!" They both saluted and disappeared down the corridor.

Celestia hovered low over her sister in worry, "Why does Luna have the condition now?" Nurse Bluebell stared at the sun princess with no words to answer her with. The two froze when they heard another voice in the room, "S-he saved m-e....." A frail yet audible voice came from the bed where the Pegasus lay. Celestia walked over to her bedside and saw that the young mare had just woken up. The princess thought to ask her more about what she meant by that, but she knew better. "Oh Lavender.... we were worried about you. How are you feeling?" The White alicorn mare with wavy aurora hair allowed the mare time to get herself together as much as she could. Moaning from slight discomfort as she tried to sit up but ultimately decided against it when it caused her pain. "Sore....mmm..." Inhaling she turned her head to face Celestia, "Where's Luna..... is..... she ok...?"

Wham! The door flew open as the doctor bolted in to check on the night princess. Lavender looked at the princess with worry, ".....she's not..... is she.....?" Celestia lowered her head solemnly as she whispered, "No.... I'm afraid not... My sister now has the same condition you had a few minutes ago.... and we don't know why." Looking up at the mare sitting up in bed against the white pillows with a tired look in her face, "Unless.... you can shed some light on the situation Lavender Rain? What happened before we got here Lav?" Celestia asked with concern written all over her pale face.

The young mare stared into space as she thought about what she remembered. "Well... I remember the book that Zecora gave me. I remember..... being taken over by some magical force..... then... I was trapped in some sort of magic void.... I think time moved differently in there too as I had only just got pulled inside when I ran into Luna who came to rescue me the first time. Then it went black.... the last thing I recall is hanging in mid air all chained up and drained of all energy. Then..... Luna came....." Celestia listened carefully, "What happened with Luna?"

"She saw me helpless and faced down the soul that attacked me. The next thing I know, she demanded for the 'queen'... to take her instead. Then I woke up but I couldn't control my own body. So I panicked..." Celestia's eyes widened, "Wait.. so you're saying that Luna essentially SWITCHED places with you??" When she saw tears welling up fast in the mare's eyes, the sun princess knew the heart-touching yet horrible truth. Luna had sacrificed herself to save her friends. And now her own sister was in grave danger of being lost forever.

Author's Note

When word gets out that the Night Princess is in grave danger after having saved Lavender from the Hypnosian Queen's soul. It's up to Lavender, Twilight and their friends to find a way to completely destroy the corrupted soul before it causes any more trouble that threaten the lives of ponies.