In what ways does The Cursed Child contradict established Harry Potter canon?

Question

For those of you who don't know, Jack Thorne, has written a script called Harry Potter and the Cursed Child, which is set nineteen years after J.K. Rowling's Harry Potter books. As to be expected there are several contradictions with pre-existing canon.

By canon I mean things from Rowling. (i.e. DVK's answer, levels 1-6)

I'll be pretty liberal in counting contradictions, but the more concrete it is, the better.

What discrepancies exist between The Cursed Child and existing Harry Potter canon?

Answer 1

Note that many of these can be answered up, one way or another.

• Platforms 9 and 10 are separated by a metal barrier, not a brick wall

  He wheeled his trolley forward cautiously until it was right against the barrier and pushed with all his might. The metal remained solid.
  _{(Harry Potter and the Chamber of Secrets - Chapter 5)}

  GINNY: All you have to do is walk straight at the wall between platforms nine and ten.
  _{(Harry Potter and the Cursed Child - Act one, Scene one)}

• Albus is a Quidditch fan

  Ginny Potter, who is sitting close enough to read everything my Quick-Quotes Quill is scribbling, informs me that Albus is a great fan of Brazilian Chaser Gonçalo Flores.
  _{(Pottermore - Quidditch World Cup Final)}

  ALBUS: Are you clapping her too? We hate Quidditch
  _{(Harry Potter and the Cursed Child - Act one, Scene four)}

• People have left the Hogwarts train

  ‘The only people in real danger are the ones whose friends and relatives on the outside are giving trouble. They get taken hostage. Old Xeno Lovegood was getting a bit too outspoken in The Quibbler, so they dragged Luna off the train on the way back for Christmas.’
  _{(Harry Potter and the Deathly Hallows - Chapter 29)}

  TROLLEY WITCH: Never — never — have I let anyone off this train before they reached their destination. Some have tried — Sirius Black and his cronies, Fred and George Weasley. ALL HAVE FAILED. BECAUSE THIS TRAIN — IT DOESN’T LIKE PEOPLE GETTING OFF IT . . .
  _{(Harry Potter and the Cursed Child - Act one, Scene eleven)}

• McGonagall is no longer headmistress

  MV: Okay. Number one, 19 years later, who's the headmaster at Hogwarts?
  JKR: Well, it would be someone new. Erm, McGonagall was really getting on a bit. So someone completely new. But if I ever do the encyclopedia, I'm promising I will give details.
  _{J.K. Rowling One-on-One with the Today Show (NBC), July 2007}

  HOGWARTS, HEADMISTRESS’S OFFICE
  HARRY and GINNY stand in PROFESSOR McGONAGALL’s office.
  PROFESSOR McGONAGALL: And we don’t know where in the Forbidden Forest?
  _{(Harry Potter and the Cursed Child - Act two, Scene three)}

• Hogwarts fireplaces cannot be entered via the Floo Network

  A return to the unregulated travel of the past was impossible, and yet a more secure route into the school (for instance, permitting a fireplace that might be officially entered by Floo powder) was strongly resisted by successive Headmasters, who did not wish the security of the castle to be breached.
  _{(Pottermore- Hogwarts Express)}

  HOGWARTS, HEADMISTRESS’S OFFICE
  (...)
  Suddenly there is a rumble in the chimney. PROFESSOR McGONAGALL looks at it, concerned. Then HERMIONE tumbles out.
  _{(Harry Potter and the Cursed Child - Act two, Scene three)}

• Draco and Harry are not destined to become friends

  All of this left me in the unenviable position of pouring cold common sense on ardent readers’ daydreams as I told them, rather severely, that Draco was not concealing a heart of gold under all that sneering and prejudice and that no, he and Harry were not destined to end up best friends.
  _{(Pottermore - Draco Malfoy)}

• Rose has Ron's hair, not Hermione's hair

  Almost all of the Weasley family are supporting Brazil. Certainly nobody can have expected Ronald to cheer on his wife’s ex-boyfriend. Both his children – Rose, who appears to have inherited her father’s unfortunate hair, and Hugo, who has his mother’s bushy locks – are decked out in green.
  _{(Pottermore - Quidditch World Cup Final)}

  There’s cheering. Particularly from a nervous-looking girl at the edge of the crowd—this is YOUNG HERMIONE (played by the same actress as plays ROSE). It is noticeable that the cheering for HARRY is slightly less than that for CEDRIC.
  _{(Harry Potter and the Cursed Child - Act two, Scene seven)}

• Madam Pomfrey is no longer Matron at Hogwarts

  Until recently the pair lived above the Leaky Cauldron in London, but rumour has it that Hannah has not only retrained as a Healer, but is applying for the job of Matron at Hogwarts.
  _{(Pottermore - Dumbledore's Army Reunites at the Quidditch World Cup)}

  HARRY: He’s been out twenty-four hours, mostly in order so Madam Pomfrey could reset his arm. She said it was the strangest thing, it’s like it was broken twenty years ago and allowed to set in the “most contrary” of directions. She says he’ll be fine.
  _{(Harry Potter and the Cursed Child - Act two, Scene eight)}

• James has the Marauders Map, not his father

  Courtney: What child did Harry give the Marauders Map to if any
  J.K. Rowling: I've got a feeling he didn't give it to any of them, but that James sneaked it out of his father's desk one day.
  _{(J.K. Rowling and the Live Chat, Bloomsbury.com, July 30, 2007)}

  HARRY: This map will reveal to you where my son is at all times — I expect you to use it. And if I hear you don’t — then I will come down on this school as hard as I can — using the full force of the Ministry — is that understood?
  _{(Harry Potter and the Cursed Child - Act two, Scene ten)}

• Voldemort does not let people use his name.

  “Nope, not jesting,” said Harry, his eyes flicking from Death Eater to Death Eater, looking for a weak link, a space through which they could escape. “How come Voldemort wants it?”
  Several of the Death Eaters let out low hisses.
  “You dare speak his name?” whispered Bellatrix.
  _{(Harry Potter and the Order of the Phoenix - Chapter 35)}

  POLLY CHAPMAN: Mudbloods, of course. In the dungeons. Your idea, wasn’t it? What’s going on with you? Oh Potter, I’ve got blood on my shoes again . . .
  She bends and carefully cleans the blood off her shoes.
  Like the Augurey insists — the future is ours to make — so here I am, making a future — with you. For Voldemort and Valor.
  _{(Harry Potter and the Cursed Child - Act three, Scene two)}

• Ron is an accomplished auror, not an idiot

  In the immediate aftermath of the battle Weasley, whose famous ginger hair appears to be thinning slightly, entered into employment with the Ministry of Magic alongside Potter, but left only two years later to co-manage the highly successful wizarding joke emporium Weasleys’ Wizard Wheezes. Was he, as he stated at the time, ‘delighted to assist my brother George with a business I’ve always loved’? Or had he had his fill of standing in Potter’s shadow? Was the work of the Auror Department too much for a man who has admitted that the destruction of He Who Could Not Be Named’s Horcruxes ‘took its toll’ on him?
  _{(Pottermore - Dumbledore's Army Reunites at the Quidditch World Cup}

  I’m armed and — entirely dangerous and seriously advise you —
  He realizes his wand is the wrong way around and turns it right.
  To be very careful —
  _{(Harry Potter and the Cursed Child - Act three, Scene six)}

• The Potters house was protected by a Fidelius Charm

  Well, of course, You-Know-Who wasn’t an easy person to hide from. Dumbledore told them that their best chance was the Fidelius Charm.”
  “How does that work?” said Madam Rosmerta, breathless with interest.
  Professor Flitwick cleared his throat. “An immensely complex spell,” (...) As long as the Secret-Keeper refused to speak, You-Know-Who could search the village where Lily and James were staying for years and never find them, not even if he had his nose pressed against their sitting room window!”
  _{(Harry Potter and the Prisoner of Azkaban - Chapter 10)}

  SCORPIUS: And here it is —
  ALBUS: The home of James, Lilly, and Harry Potter...
  _{(Harry Potter and the Cursed Child - Act four, Scene three)}

• Polyjuice takes one month to make

  “Well, since the fluxweed has got to be picked at the full moon and the lacewings have got to be stewed for twenty-one days . . . I’d say it’d be ready in about a month, if we can get all the ingredients.”
  _{(Harry Potter and the Chamber of Secrets - Chapter 10)}

  ALBUS: Polyjuicing. And I think Bathilda Bagshot may have all the ingredients for Polyjuice in her basement. We can Polyjuice into Voldemort and bring her to us.
  _{(Harry Potter and the Cursed Child - Act four, Scene ten)}

• Bellatrix showed no signs of being pregnant during Deathly Hallows

Answer 2

Keep in mind none of these is a certain contradiction. There may be explanations for each one. But there were several possible inconsistencies that struck me upon a first reading.

• When Professor McGonagall mentions that the lacewing flies and boomslang skin, essential ingredients for Polyjuice Potion, are missing, none of the various people in the room who have made Polyjuice Potion before seem to see any significance.

• When various people go back in time, they can see the Potter house, even though the Fidelius Charm is in effect and they have not been given the location by the Secret-Keeper.

• In the evil alternate universe, where Voldemort won the final battle, the name "Voldemort" is used liberally, even by his dedicated servants. There is even a holiday that incorporates his name. The book Voldemort would likely never have tolerated this.

Answer 3

In the second alternate reality Harry dies, but he can't die if Voldemort is still alive as Lily's blood runs in voldemorts veins (from his regeneration) and this tethers Harry to life.

Answer 4

1. The whole secret keeper business should not have allowed any of the cast (save Harry) to be able to see the Potters house.

   Pettergrew can inform people, but the charm is not his to cast. He can't erase it. The only reason others were able to come after to the ruins of the home was because the house, and thus the secret, was destroyed.

2. But here is a big thing; Why was Snape alive in the alternate future?

   I know there is the whole "flux of time" thing going on, but Harry was still hunting Horcruxes (and the whole business with the hallows). That was the whole reason there even was a battle for Hogwarts. Dumbledore still likely died by Snape's hand (which is the reason he was trusted for so long).

   If Harry died in the battle, that means he wouldn't have died in the battle of the seven potters. The only reason he survived that was his wand, which prompted Voldy to search for the Elder wand. And eventually kill Snape.

   There is no reason why the things they altered would have saved Snape. Even with the explanation that humiliation was enough to get Cedric to become a Death Eater (the kid willingly gave up a win for a tie in the original Triwizard Tournament because he was so honorable, and was pretty much as clean/moral as they come at Hogwarts), that doesn't explain why he was still around when Voldemort still would have killed Snape (even if it was a world in which Malfoy killed Dumbledore, why is Malfoy still around?). He wanted that wand bad.

   Snape should have been dead.

Answer 5

After reading Cursed Child, the only major issue i noted was,

Harry, Albus, Severus, and gang all go back in time to the night Harry's parents are killed by Voldemort. They are all able to see the Fidelous charm protected Potter house, and listen to Voldemort killing Harrys family.

Other then this, everything else can simply be hand waved by Magic.

Answer 6

SPOILERS

Since the reason Voldemort lives is because Neville wasn't alive to kill Nagini, I think we can assume Harry went through with his 'sacrifice' and survived because of the tethering thing. But he ultimately died when he went against Voldemort the 2nd time that night because Voldemort still had Nagini. I doubt he can be protected by his mother's blood an unlimited number of times...maybe just the once?

Answer 7

Another flaw to me is when they traveled back in the time when Voldemort broke in the Potter's home in the dead of the night, and effortlessly murdered Harry's parents and attempt to murder Harry himself. How is it that they returned to the present? Remember the Prisoner of Azkaban? Once you click on a time-turner one time, you cannot reverse the time to the present until you waste one hour of your life regardless of what your doing.

That's a part in the Cursed Child I don't understand. Oh, in case I haven't told anyone I never read it, but have heard of it. I apologize if I get some facts wrong.

Answer 8

Many 'good' characters, including Hermione, refer to Voldemort as 'The Dark Lord' rather than by his name or HWMNBN. Only his followers referred to him this way.

Answer 9

Albus believes that his father, Harry, seems to be dismayed that he ended up in Slytherin House.

Harry says to Albus quite pointedly that he would be proud of him if that did in fact happen:

“Albus Severus,” ... “you were named for two headmasters of Hogwarts. One of them was a Slytherin and he was probably the bravest man I ever knew.”
“But just say —”
“— then Slytherin House will have gained an excellent student, won’t it? It doesn’t matter to us, Al.
^{-Harry Potter and the Deathly Hallows, Epilogue (Nineteen years later).}

But in The Cursed Child a lot of Albus' problems stem from his belief that Harry isn't happy with this turn of events:

HARRY: Is that how I make you feel?
ALBUS looks at his dad, trying to figure him out.
ALBUS: I don’t think Scorpius said, but when we returned after failing to fix the first task, I was suddenly in Gryffindor House. Nothing was better between us then either — so — the fact that I’m in Slytherin — that’s not the reason for our problems. It’s not just about that.
HARRY: No. I know. It’s not just about that.

Not sure why Albus thinks this is a problem.

Answer 10

First of all, we should remember that the script that was published and released was NOT the finished story. It was the FIRST DRAFT that was given to us. It was the Special Rehearsal Edition. The final story with the repairs and tweaks will be published in 2017 as the Definitive Collector's Edition. The Special Rehearsal Edition was for rehearsal of the play and the previews. The tweaks were suggested by the audience of the previews. The previews were the showings that happened before the play officially released to ask for reviews and changes in the plot and the special effects. So, in fact there are many different versions of the script with slight changes as the previews progressed. The changes being from dialogue to major events alongside special effects of the play. So, there are 20, 30 or maybe even more versions of Harry Potter And The Cursed Child with varying plot and story contradictions lying out there somewhere, either at the theater where the play is going on, or at JK Rowling's or at John Tiffany's or at Jack Thorne's house. The final, canon version of the story will come out next year. Atleast JK Rowling gave us something. If she had decided to print the Definitive Collector's Edition only, we would have gotten nothing this year, except for Fantastic Beasts. The final story was prepared around the 22nd of July, so the final story would have taken atleast months to be published worldwide and we would have had to wait till next year for the story. Atleast we got something, even it wasn't canon and most of the story will be replaced by something else. So, in conclusion, most of the contradictions will have been repaired by the next edition of the Harry Potter and the Cursed Child.