This story is inspired by the fanfiction story titled 'Guy Fawkes Day' by MisterQ. Go read it! Space Expansion Charms are unforgiving when misused in that story.
Just writing a story for fun and enjoyment. Thanks to Rowling for giving the world Harry Potter and his friends (and enemies). She owns everything and I'm just imagining shapes in the clouds on a summer day.
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August 1994When Harry Potter arrived at the Burrow before the World Cup, and talked with Ron, his friend had groused about not having Hermione's help (to copy her papers) to complete the summer assignments. The red head didn't understand why the young witch would miss her parents.
"Hermione and her parents wanted to stay with each other the whole summer," Harry explained.
"But they're just muggles," argued Ron. "You don't miss your muggles!"
"No, but my relatives and I don't love each other," Harry reminded Ron. An eavesdropping Mrs Weasley parroted Albus Dumbledore's lines about Harry's aunt and uncle really loving him.
Under his breath, Harry muttered, "No one listens. No one cares. Just like Dumbles and my relatives."
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The Usual Weasley ScheduleTo begin his fourth year at Hogwarts, Harry Potter prepared to use the floo network to travel from the Leaky Cauldron to Kings Cross Train Station on the morning of 1 September. He would travel with the Weasley family after everyone stayed overnight in the tavern after finishing some last-minute shopping for potion ingredients. The next morning, true to form, Ron and Ginny weren't ready when it was time to depart through the green flames of the fireplace for station.
Everyone in the family groaned when they learned the youngest Weasleys left their textbooks at home rather than packing them in trunks the day before. And Ron and Ginny didn't notice the absence of the books until it was time to leave for the train station. Following the usual shouting match between Ron and Ginny and their mum that left everyone's ears ringing, Mrs Weasley declared she would take the two children back to the burrow to collect the textbooks, and then join the others at the station.
While everyone in the Leaky Cauldron waited, Mrs Weasley continued to lecture her two youngest children loudly before leading them through the green flames in the fireplace. Despite the grumbling of other patrons who needed the floo or simply wanted to slip around the crowd of gingers blocking the centre of the tavern, Mr Weasley sent George, Fred, and Harry through the green fire before he followed them.
Harry picked himself up off the receiving room floor at Platform 9¾ and thanked Mr Weasley for hosting him for the last few days, the ticket to the World Cup, and getting him to the train this morning. Fred and George disappeared into the crowd of students getting on board the Hogwarts Express, looking for their friends from Gryffindor.
"I'll go outside Platform 9¾ to meet Hermione and bring her through the portal," Harry told the others.
"Put your trunk on the train, Harry," Mr Weasley said. "Is it secured and locked?"
"Yes sir," Harry replied. "The other night, Percy taught us all how to use the new locking spell that's tied to the wizard's wand."
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Percy's Warning about Expansion CharmsArthur smiled at the memory of his third son's visit at the Burrow on 30 August. Newly hired as a clerk at the ministry, Percy taught the twins and others how to use a new locking charm. Fred and George had immediately began considering how to deconstruct the charm, Ron had groused about 'Perfect Percy' and his new job at the ministry, but Harry and Ginny were pleased.
Percy reminded them to be especially careful because of the danger of mixing this locking charm with any space expansion charms used to make the interior of magical trunks larger. George and Fred put their heads together and agreed to remember the admonition.
Fred explained, "Bill lectured us for an hour about those charms and how we can't mix them with other charms. This locking charm would react badly with the expansion charm. Most charms don't function properly if they're compromised."
"What would happen?" asked Harry.
"An explosion for certain!" Percy said. "Ask Professor Flitwick about it after class one day. He's one of the charm masters who developed this locking charm."
Ignoring the danger of mixing expansion and locking charms, Molly had questioned the wisdom of the twins being able to lock their trunks where she couldn't inspect them, but Harry was secretly pleased that none of his galleons, chocolate frogs, socks, and pants would disappear into Ron's trunk this year.
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Meeting the Creevey and Granger FamiliesOn Platform 9¾, there were many children already in the train and Harry found Neville Longbottom near the front of the train. Greeting Neville as he entered the compartment, Harry lifted and slid his trunk into the overhead compartment next to Neville's.
"I'm going outside to meet Hermione," Harry told the other fourth year boy. "Want to come?"
"No. I'll stay here and protect our trunks from Slytherins and other troublemakers," replied Neville.
Grinning, Harry explained about the new locking charm and promised to teach it to Neville as soon as the train started on the journey to Hogwarts.
"Where's Ron?" asked Longbottom.
"He and Ginny forgot their schoolbooks at the Burrow," explained Harry. "Mrs Weasley took Ginny and him back to get them."
"So, they'll have to run to catch the express as it leaves the station…like every year," Neville quipped.
"Yeah, like every year."
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It was different to pass through the portal and visit the muggle side of the station on the first of September. Harry immediately found the Creevey family there. Colin and Dennis were sharing hugs with their parents and sisters before stepping through the portal to vanish until Christmas holidays.
"Harry! Hi!" shouted Colin.
"We got an owl this summer, Harry," declared Dennis. "His name is Barnacle, so Hedwig won't have to carry all our letters home this year."
"There'll be lots of letters for both owls to carry home this year," Harry replied. "Where is Barnacle?"
Dennis explained, "Hedwig came by the house this morning and they flew off to Hogwarts together."
"I wondered where she'd flown off too," Harry admitted.
"Harry, can I introduce my parents?" asked Colin.
Embarrassed but willing, Harry was introduced to Mr and Mrs Creevey and the two younger sisters. He found himself envious of the warm feelings evident among the Creevey family and took a deep breath before wishing them a safe drive home and turning to look for Hermione. Colin and Dennis vanished through the portal, heading for the front of the train and a compartment near the one Harry described where Neville waited.
It was another fifteen minutes before the Granger family appeared from the entrance to the car park with Mr Granger managing the heavy trunk while Hermione fussed with her mother. Harry had been disappointed that Hermione missed the World Cup (but he was glad she missed the aftermath when a group of Death Eaters attacked the crowd). Her letters stated that her parents missed her while she was gone to school, and they wanted her with them for the entire summer.
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An ExplosionOutside Platform 9¾ Harry approached the Granger family and was greeted by the usual Hermione hug, and friendly hellos from her parents, when there was a loud explosion behind them.
The loud blast caught everyone off guard. The persons in the station flinched and then ducked. Mr Granger grabbed his wife and daughter to pull them into a store front and Harry followed, his wand slipping into his hand. Mrs Granger held Hermione close while Mr Granger and Harry tried to watch different directions for more dangers. Some rubble fell out of the sky and there were sirens and whistles going off all around the station.
"What was that?" Mrs Granger asked.
Mr Granger replied, "I don't see anything."
Harry paused before he said, "Mr Granger, I see smoke and flames over the wall. Platform 9¾ blew up."
Immediately, the grownup said, "Why can't I see it?"
"Notice-me-not charms and spells I guess," Harry said. "Here, grab my hand and you'll be able to see it."
Grabbing the teenager's hand, allowed Mr Granger to see the smoke and fire. After a moment, the man informed the teen, "I don't think it was the entire platform. The smoke is confined to one area – is there a building there on the platform?"
"Yes sir," Harry replied. "There's a receiving room where people arrive via apparition, portkeys, and floo."
"The floo? In the fireplace? That floo?" asked Mr Granger.
"Daddy, I told you about people being able to step through the fireplace," Hermione reminded her father. "They throw in floo powder and call out their destination before stepping into the flames when they turn green. They are magically carried to their destination in an instant."
Seeing the man's scowl, Harry explained, "None of the magical methods for moving around are comfortable – they're just quick so wizards put up with getting thrown on the floor."
They watched the smoke for a moment before Harry asked, "How do you know about explosions, sir?"
"I was in the navy and served in the Falklands War. There were enough explosions there to learn a few things."
"So, are our friends on the train alright?" pressed the teenager.
Finally understanding, the adult replied, "I imagine so."
At that moment three Aurors appeared from the car park – their red robes identified them as magical police but their notice-me-not charms meant the confused muggles wouldn't see them while looking for the source of the explosion. Spotting a couple of magical children, one tall, black man peeled off from the others to check on Harry and the muggleborn family he stood with.
"Auror Kingsley Shacklebolt," the man said to identify himself. "Anyone hurt? Can you tell me what you heard and saw?"
"Dr Henry Granger," replied Mr Granger before he explained what they'd heard and what he'd seen after taking Harry's hand. "The smoke is not coming from the train tracks."
"Thank Merlin," the Auror murmured. "Let me see what's going on inside the platform."
The man vanished through the portal and the Grangers and Harry stepped back outside the store to find seats at a coffeeshop where Mrs Granger purchased drinks and pastries for the four of them.
"We'll miss the train!" Hermione worried. "How can we get to Hogwarts this evening?"
Harry kept his eye on the portal to the platform but replied, "There's lots of ways to get to the castle, Hermione. The Aurors can take us by apparition, we can go to the Leaky Cauldron and use the floo there to go to Three Broomsticks in Hogsmeade, or we can call the Knight Bus."
"What's the Knight Bus?" asked Mr Granger.
Harry grinned and explained, "It's a wild ride on a bus that feels like a roller coaster that goes faster than a jet aeroplane. We'd be at Hogwarts in fifteen or twenty minutes."
"Wizards don't have any common sense," Hermione's mother commented and while her daughter frowned, Harry nodded in agreement.
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