Fog wrapped the castle. Not the cloudy vapor of an early-spring morning, but the fog of forgetfulness. It became as though thoughts of the past slipped through people’s fingers. Oh, not that they couldn’t remember when they tried, but more that they lost the desire to keep those memories.

I knew the dragons were to blame, because they were what people forgot the most. I’d mention them and receive a blank stare in response.

“Dragons?” they’d gasp, blinking in astonishment. “There is no such thing as dragons!”

How quickly they forgot. When my father, Magnificent Wray, had collared those dragons, they’d celebrated. When he’d set the dragons to build the Star Castle, they’d cheered. But when he passed away, the dragons became a myth in a matter of months. A foggy, uncertain idea that was best left unthought. Only a few people retained the memories of those days. A handful held the precious trickle of thoughts: vital notions of dragons, magic, and danger.

I am one of the few.

--Lady Amber DeVere, My Father, Magnificent Wray

The key burned a hole in my apron pocket. It was small and silver, with a starburst inscribed on its bow. And although dozens of keys hung in the Head Steward’s office, they were ordinary. None had a starburst. This key had once belonged to Magnificent Wray, my ancestor and the architect who had designed the castle. A man of mystery and magic. The starburst was his emblem, and that made this one special.

The bow held the smallest spark of magic. I hadn’t noticed it until I pressed my thumb down hard, but it was there. Which made me wonder: Did the lock it fit hold a greater magic? A stronger, more powerful force? What would happen when the two met? And what lay behind that lock?

Did this key unlock a treasure?

That question fired my imagination with possibilities.

“Gold? Jewels? A magic ring?” I mumbled under my breath. “Magnificent Wray’s secret workshop? What?”

“Quiet,” Gillian whispered, peeking around the corner ahead of us.

I rolled my eyes. We were pressed against a wall outside the corridor to the Princess’s suite. It was early, and everyone in the castle was busy getting ready for the day. Our chances of running into someone were small. But the past weeks of slinking around together looking for the keyhole had given Gillian a taste for stealth. She made each search an ordeal of hand signals, tiptoeing, hiding behind curtains, and flattening ourselves against walls.

It had gotten a bit ridiculous. But every keyhole beckoned, Try me.

Each chance we got, we hightailed it to the next tantalizing lock. One of us would be the lookout while the other tried the key. So far we hadn’t had any luck. But Roger, the First Stable Boy, was right: it was too small to open doors. And we’d discovered it was too big to open jewel cases.

We were no closer to finding out what the key did open than we’d been when we started. There were at least a million locks in the Star Castle. We’d given the key to Roger, and he’d tried every keyhole in the stables and the outbuildings. Nothing. But it had to open something, and we planned to keep searching until we found out what.

Ahead of me, Gillian braced herself to sprint for the next lock. Her dark curls were swept back with a ribbon, her brow furrowed in concentration, her brown eyes fastened on the prize.

“On the count of three,” she whispered. “One--”

“Three,” I said, eager to arrive at the next lock.

I bounded around the corner and down the corridor. Past the ornate doors of the Princess’s suite and straight to the double doors leading to the soon-to-be King’s suite. It had been closed up since the death of Princess Mariposa’s father, years earlier. Until now.

Gillian hurried to catch up with me.

“Darling, wait!” she called.

The doors to the King’s suite were painted to resemble a view from a window. The painting portrayed Eliora by the White Sea, this very kingdom. The details were stunning. A mountain rose above the sea. Birds soared. Ships drifted in the harbor. The city sat nestled in its cove. And the Star Castle crested a rise that climbed to the mountain’s top. I squinted at the brushstrokes: every leaf and stone was executed so that you felt you could reach out and touch it.

“It’s a special kind of painting,” Gillian said, panting a little. “Trumpet oil, Baroness Azure called it. I think that’s a kind of paint. Anyway, it’s supposed to fool you into thinking it’s real.”

Gillian had the habit of repeating what the Baroness told her. Although not necessarily correctly.

“Trompe l’oeil,” I said. “It’s a style, not a paint.”

“Sure,” she agreed affably.

She reached out and turned the castle, which rotated because it was actually the doorknob. The enameled metal piece fit so neatly into the painting that you didn’t suspect it was there. She pulled the door open and walked inside.

“The Baroness said,” she began, “that the Princess’s suite used to be the Queen’s suite when there was a queen. But now the Princess uses it, since she’s like a queen. Only not. But she will be.”

Princess Mariposa had stayed a princess since her parents’ death because her father’s will stated that she could be queen only upon her marriage. In a matter of weeks, there would be a wedding, a coronation, and a ball! The entire castle was abuzz over the upcoming events.

“I hope the Baroness said something we don’t already know,” I replied.

“She says lots of stuff.” Gillian paused a moment to admire the suite’s anteroom, with its three doors. “The King’s suite is a mirror image of the Princess’s.”

A forest flowed around me, holding the walls, the floor, and the ceiling in its painted leafy embrace. The doors nearly melted into the walls. A bluethroat eyed me from its perch in a tree. The sun dappled its little brown head and the white-tufted blue patch under its beak. A rabbit hid in a hollow.

“The fastest way is to go straight through the bedroom,” Gillian added.

She opened the center door, breaking the illusion, and stepped through. I followed her into a room devoid of furniture, where the scents of turpentine and lemon oil tickled my nose. The walls glistened with fresh paint: royal blue, Prince Sterling’s favorite color. The carved crown moldings glinted with gold. The marble floor gleamed.

“It’s being redecorated for Prince Sterling,” Gillian explained, gesturing at the ladders and buckets scattered about the room. “New furniture, drapes, carpet. Well, all except for the reading room, of course.”

“Uh-huh,” I said.

“Prince Sterling declared that it was already perfect. He said don’t change anything but the drapes,” she continued, following me. “Mind your step.”

I nearly stumbled over a rolled-up carpet. Gillian caught me with a grin. Threading our way around buckets and ladders, we reached the next door. Beyond it was a lounge. A partially finished mural wrapped the walls, but Gillian didn’t waste time admiring it. She raced to the last door and threw it open.

“Here it is,” she announced, as if I wouldn’t grasp where I was. “The reading room!”