The Water Dragon hooked its head over the side of the tank and pulled itself forwards. Alex and Bridget gave the rope a final jerk and the dragon wriggled over the lip of the glass. It rolled in the air as it fell, turning its armoured back to break the fall. There was no choice but to throw out their arms and catch it.

It was like trying to catch a cannonball. The weight of the dragon knocked them off their feet and left them pinned underneath it.

“Seize them!” bellowed Mayor Parch.

“I’m not sure,” said Zoey through the walkie-talkie, “but I think you’ve been rumbled.”

Everybody seemed to snap into action at once. The guests surged backwards in terror, jamming shoulder-to-shoulder in the archway and blocking the guards behind them.

It was the only chance they would get to escape, but Alex was completely trapped by the Water Dragon. Even Bridget, heaving with all her might, couldn’t get it off them.

Guards managed to push through to the front of the crowd. The sight of the dragon loose from its tank was enough to make them advance with caution.

A rumbling started deep inside the Water Dragon’s body, a seismic groan like tectonic plates shifting deep under the seabed. It grew into a resonant quaking, as if the dragon’s scales were vibrating together in terrible concert.

Alex felt his skin begin to tingle. Closing his eyes, he felt the dragon’s power lash against him. It was weak, but it reverberated along the invisible thread that connected them, teasing out the power inside him, drawing on it to charge up its own. It made his whole body hum with giddy energy.

“Get ready,” he said, flexing his fingers.

Beyond the archway, the tanks lining the thoroughfare began to vibrate. The water inside stirred and sloshed against the glass.

Behind the crowd he spotted Callis, looking on calmly amid the commotion. The poacher was the first to notice the waves sloshing inside the tanks. Their frames creaked as water strained against them. Cracks spidered through the glass. Iron popped and snapped. The crowd turned to watch the water beat mercilessly against its prisons.

The membrane around the Water Dragon’s neck puffed full. The trickle of power inside Alex became a torrent.

Every tank ruptured at the same moment. But instead of raging along the avenue, the water picked itself up into living shapes, liquid legs tottering onto the path. The figures carried the tank ornaments with them: the shape of a man lumbered forward with a brass diving bell for a head, spears of rock strengthening its aqueous arms as it lunged at the guests. Tendrils of weed flailed around a stone serpent’s head, the water supporting it plaited into a slithering snake’s body. A shark with blazing gems for eyes and the broken hull of a model battleship for a fin snapped its watery jaws.

The liquid army advanced on the crowd from all sides. A few people tried to fight back, swinging canes and bejewelled handbags, but they splashed harmlessly through the bodies.

“I can’t swim!” trilled a woman as the serpent swallowed her whole, leaving her to peer out from inside its transparent body.

“This suit is cashmere!” complained a man as the shark chomped wetly on his legs.

Mayor Parch cowered as a figure with a treasure chest for a head, the lid flapping like a gaping mouth, lurched over him.

“Help me!”

The mayor’s guards dodged the stampeding crowd to run towards the dragon.

Amid the chaos, Alex saw Callis study the scene, before slipping away out of sight.

“We’re still trapped!” said Bridget.

Alex laid a hand flat on the Water Dragon’s scaly hide and let its power wash through him once more. It connected him to the ocean – to the currents that surged through it, the pressure of the pitch-black bottomless deep, waves crashing against the shore. Together they had the strength to wield it all.

The water inside the giant tank beside them lifted itself up into a heaving swell and slammed against the glass.

“Whoa!” shouted Anil, still afloat inside.

Imprisonment away from the ocean had kept the Water Dragon separated from its full power. The new bond between the dragon and Alex amplified it, like lightning snapping at storm-tossed waves.

Another wave smashed against the side of the tank hard enough to make it collapse. A miniature ocean rushed after it as a surging wall. The watery figures collapsed into the wave. The guards made a final run towards them but were swept off their feet.

The wave held together and reared up like a living creature. Alex felt the dragon’s power threading through it, wrapping a protective bubble around him, Bridget and Anil. The irrepressible deluge picked up the Water Dragon and washed them all towards the back of the aquarium.

The force of the water broke open the glass outer wall. They held tight to the dragon’s armour plates as the torrent carried them careening down the slope beyond. Water wrapped around them, cushioning them against the bumps and dips in the hill, leaving a pocket of air so they could breathe. The waterfall bore them whipping past bushes and scrub in the darkness.

“The water will protect us!” Alex shouted. “Trust it and we’ll be okay!”

Night had fallen while they were in the aquarium and the lights of the houses on the street below briskly drew closer, blurring across his vision as they reached top speed. After several more tumultuous seconds the slope began to level out before it reached the road. The wave held firm and tall, letting them all sink through it to rest safely on the ground, before the power dissipated and the water washed away across the tarmac.

“That was amazing!” Anil said. “Can I go again?”

Bridget patted over the Water Dragon. “Is it okay?”

The dragon’s body heaved with laboured breaths, but the wave and its hardened scales had protected it from injury. It lay unravelled at the edge of the road like a gigantic over-cooked noodle, its power spent. Alex knew how much it was relying on them now.

A dog barked on the pavement behind them. In the light of the full moon overhead, they found Mrs Bilge rooted to the spot, Cannonball hiding behind her trembling legs.

Alex picked up the sodden rope. “We’re just taking our new dog for a walk.”

Mrs Bilge’s voice quivered. “What breed is he?”

“Um…aquatic?”

Bridget patted the Water Dragon’s mighty head. “Good boy.”

With a huff, Mrs Bilge hurried past, tugging Cannonball after her before the dog ended up as a midnight snack.

“What do we do now?” asked Bridget as soon as the old lady was gone. “We can’t drag it all the way to the ocean.”

They were so close! Only a few streets lay between them and the refuge of the bay. But it was enough to leave them stranded.

A cacophony of bells like wind chimes clanging in a tornado sounded from the end of the street. Wheels squealed to accompany it.

The ice cream van skidded around the corner, chimes playing at full blast. It screeched to a halt in front of them. Grandpa shut off the engine and Zoey jumped out of the cab. She raised a hand to catch her drone as it dropped out of the sky.

“Need a lift?” she said.