A smoking hourglass was lit up in fire across the front of the alehouse. The building was engulfed in seconds. People started running away, shouting.

“Ivy, help me with these!”

She turned to find Mr. Littlefair staggering out of the Cabbage Moon carrying four buckets of water. Ivy hurried over and grabbed two. Alexander followed, with more buckets.

“Hurry!” Mr. Littlefair shouted. “We need to douse the flames!”

“What kind of fire is that?” Ivy asked. The flames weren’t orange; they were plum and crimson colored, with licks of black. They seemed to be consuming the place more quickly than regular fire could.

“Blackfire,” Mr. Littlefair said. “Deadly. It can only be made using mixology.”

Ivy placed one bucket at her feet and swung the other toward the fire. Customers were still running out of the building as the water hit.

“It’s no use,” Alexander shouted. “Look!” He pointed to the roof, where the fire was rapidly eating through the thatch.

Ivy grabbed the second bucket and swung it toward the alehouse just as a red-faced Drummond Brewster came barreling through the front door. He was clutching to his chest the charred framed photo of him inventing Dragon’s Breath Ale.

“SOMEBODY DO SOMETHING!” he boomed, charging out among the fleeing crowd. He grabbed a man by his lapels and began shaking him. “My alehouse is burning down! The Dragon’s Breath is fueling the flames; it’ll be ashes in a matter of minutes!”

Alexander hurried to his side, tugging on his apron. “I’m here, Pa. I’m OK.”

“Do something useful!” his father snapped, eyes still fixed on the alehouse. Ivy couldn’t help but notice the look of disappointment on Alexander’s face.

Suddenly she heard a siren. The underguard. About time.

Two black 4x4s came rumbling into the street and the remaining traders formed large circles around them. The passenger door of one opened and Inspector Smokehart stormed out and began shouting.

“Castleguards—get control of this blaze!” he commanded, pointing to the team who had just emerged from the other vehicle. Ivy noticed they had slightly different uniforms to normal underguards—a castle design was embroidered on the backs of their cloaks. “You three,” he called to the trio of constables from his own car. “Cordon off the area, get everyone inside. We need to have this blaze under control before any pyroaches arrive.”

“Pyroaches?” Ivy said.

“A race of the dead,” Mr. Littlefair mumbled, fetching more water from the tap outside the Cabbage Moon. “They can only exist in extremely high temperatures, so they live in volcanoes, incinerators, power plants—those kinds of places. You only find them in undermarts when something’s burning.”

“Are they dangerous?” she asked, filling one of her buckets.

“They eat living flesh.” Mr. Littlefair strained under the weight of two sloshing pails. “You don’t want to meet one.”

Johnny Hands had once told Ivy that smoke in an undermart was a bad omen. It made sense now.

The castleguards opened the trunk of their vehicle and each picked up something brightly colored, and carried it toward the alehouse.

“Are those buckets and spades?” Ivy exclaimed. The plastic shovels were luminous shades of pink, blue and yellow and the buckets were just like those used by children to build sandcastles at the seaside. When the castleguards were in position, some aimed their spades at the alehouse, holding them to their shoulders like rifles, while others turned their buckets upside down on the dusty road: an unending stream of sand and water spouted from the spades toward the flames.

A hand gripped Ivy’s shoulder.

“What’s going on?” Seb asked. The others came rushing through the doors of the Cabbage Moon behind him.

Granma Sylvie put a hand to her chest. “Ivy—you’re OK.” She clasped her in a hug.

“I’m fine,” Ivy said, pulling back. “I was just talking to Alexander when the alehouse burst into flames. The smoking hourglass materialized out of thin air like it had been lit on a timer.”

The underguards started shuffling back, and Inspector Smokehart appeared in the space. “We will be taking witness statements from anyone who may have seen something,” he announced. “Whether you think you did or not, it could all be important. A murderer is on the loose, and I suspect we will be adding arson to the list of charges against them.”

He caught sight of Ivy and Seb and curled his lip. “You two. Again. I saw you at the memorial; you’re making quite a habit of appearing at crime scenes. Do you expect me to believe that it is just a coincidence?”

Seb shifted his weight, eyes down. Ivy didn’t bother offering a defense; Smokehart wasn’t going to believe her.

Remembering something, she felt for her satchel and clicked the clasp shut….Amos’s journal was inside.

One of the castleguards approached the inspector, clearing his throat. “We think it’s some kind of time-delay blackfire concoction, sir. Never seen the formula before; must be the work of a highly skilled mixologist. It’ll take a good ten minutes to get those flames under control with our buckets and spades.”

The alehouse thatch was still smoking and the walls were charred, but the majority of the strange purple flames had disappeared.

Drummond and Alexander appeared in front of Brewster’s. “Well?” Drummond cried, charging up to Smokehart. “Have you found out who did this?”

The inspector stiffened. “We are just beginning our investigation, sir,” he said tightly. “You need to step aside and let us continue.”

“Step aside?!” Drummond thrust his charred photo in front of Smokehart. “Have you seen what has happened here? My reputation, my livelihood! I will not step aside! What are you doing just standing there?”

Ivy noticed that Smokehart’s neck was now speckled with blood-red dots, which only happened when he was seriously angry. She shuffled back.

The sound alerted Smokehart. “You!” His head shot around. “Don’t think you’re getting away. I want you searched.” He pointed to one of his constables, who promptly strode up to Ivy and patted her down before lifting her satchel over her head.

“Wait!” she said, pulling it back. “That’s mine! You have no right to do this!”

Seb tugged on the strap. “Oi! Give it back!”

“Excuse me,” Granma Sylvie said in a firm voice, stepping forward.

The constable scowled and swept aside his black cloak, giving a glimpse of his uncommon toilet brush. Ivy hadn’t forgotten the horrific pain she’d felt when she was attacked with one before. She hesitated before laying a hand on Seb’s elbow.

“Let him have it,” she said softly. “It’s not worth it.”

Smokehart snatched Ivy’s satchel, ripped it open and yanked the uncommon photo frame out first.

“Hold this, boy,” he barked, shoving the satchel into the arms of the closest bystander, Alexander Brewster. Ivy tried to attract the boy’s attention, but he was looking at his father. She tensed as Smokehart inspected the photo frame.

“Really, Inspector! Is this all you can think of?” Drummond protested. “Examining the contents of a little girl’s bag? You should be hunting for the real culprit. This is the work of a master criminal, not a child.”

The insult bounced off Ivy; she was much more concerned about Smokehart finding Amos’s journal. He took the satchel back from Alexander and rooted through it, dropping Ivy’s belongings one by one. She flinched when Scratch hit the dusty ground; she could see him trembling. Finally, Smokehart turned the bag upside down and shook it. Ivy studied the pile at his feet. The journal wasn’t there.

Had she lost it? If Smokehart had found it, the smoking hourglass would be all the evidence he needed to connect her with the memorial murders. More worryingly, in the wrong hands the journal could be dangerous. Amos might have recorded any number of powerful secrets inside.

Ivy tried to think back. The last time she’d seen it was when Alexander had handed it back after it had fallen out of her satchel, but in all the commotion she could have dropped it again. She scrutinized the closest bystanders; perhaps one of them had picked it up.

Seb nudged her in the ribs and nodded at Alexander. Ivy spotted the corner of Amos’s journal protruding from the pocket of his dirty apron. She relaxed and tried in vain to catch his eye. She couldn’t understand why he’d helped her, but she was thankful that he had.

Smokehart clenched his teeth, his dark glasses fixed on Ivy.

Drummond Brewster gave an exasperated sigh. “Well, I could have told you you’d find no evidence in there. Whoever’s behind this has obviously been plotting my downfall for some time.” He waved the framed clipping in Smokehart’s face. “They’re jealous of my success! See!”

The inspector looked at the uncommon photo frame in his hands. “I have a suggestion,” he said, snatching the burned newspaper cutting out of Drummond’s grasp. “Why don’t we put your special picture in this, if your frame is too damaged?”

Ivy could only watch in stunned silence as he inserted the clipping into the uncommon frame.

Instantly the dusty street was covered with an image of a stainless-steel kitchen. The crowd hushed, and Smokehart’s eyebrows disappeared below the top of his dark glasses.

The ghostly image of a fresher, thinner Drummond Brewster popped up from behind a countertop. He was carrying three bottles of different-colored liquid.

“What else do you need, son?” he called. “How about some of this silver stuff?”

Alexander walked into the room, carefully balancing a cauldron in his arms. He put it down on the stove. “No thanks, Pa,” he said. “That will dull the effect of the fire. You need just the right balance of ingredients for it to work. I’ve been experimenting with this formula. We need it to be fiery but not to burn the drinker’s throat.” He added two drops of a fizzy black liquid. The cauldron started to emit steam. “Almost there.”

Drummond peered in and rubbed his hands together. “If this works, I’ll be famous. We could take the alehouse around the world. Quick—let’s get a picture of the moment I invent it.”

Alexander kept his eyes on the contents of the cauldron, but Ivy noticed a line appear on his brow. She couldn’t believe what she was seeing. Drummond hadn’t invented the ale at all. Alexander had!

Drummond left the scene and came back carrying an uncommon snow globe while Alexander stirred the mixture with a spatula. Ivy gathered it was uncommon because the cauldron started floating.

“OK, it’s done,” Alexander said with a sigh.

Drummond grinned. “Move out of the way, then—let’s get this picture.”

Alexander stepped back, head down, and aimed the snow globe at his dad.

At that moment the scene evaporated and there was only the road before them. “That is PRIVATE!” Drummond raged, snatching the frame from Smokehart and pulling out the newspaper clipping. “How dare you!”

There was a smirk on Smokehart’s face. “My apologies,” he said. “Though I must say, that was illuminating.”