The Weasley twins interrupt the OWLs (Ordinary Wizarding Exams) in revolt against Umbridge's oppressive regime. The twins (played by James and Oliver Phelps) have been a fairly irritating staple of the franchise since The Philosopher's Stone , but they finally get a decent moment here.
It's nice to see Umbridge's authority upset, and the twins do cause disruption in truly spectacular style, flying through the Great Hall, setting off all manner of fireworks. No surprise that they go on to run their own joke shop, seen in Part VI .
From the Great Hall to the dorms
One of the most enchanting thing about Hogwarts has got to be the feasts. For one thing, they take place in the Great Hall, which is always decorated with impressive floating decorations.
After a welcome feast in the hall, a prefect escorts the young'uns to their dorms via the magic stairwell.
It's an impressive enough stairwell as it is, set inside an enormous atrium bedecked with magic talkative paintings. Charming and exciting, old-worldy yet familiar, it's like a homely fantasy fortress come to life, and it will become a permanent, familiar fixture with the Harry Potter movie-verse.
Part V is littered with disturbing dreams of Harry's, including one in which he sees the highly bizarre (and just a little creepy) image of Voldemort suited and booted at the train station.
The most shocking dream he has is the one in which Ron's ever amiable father Arthur (Mark Williams) is bludgeoned within the Department of Mysteries. Heavy stuff for a family film.
Corporal Punishment, Snape-style
Snape demonstrates a simple approach to behaviour management while Harry and Ron are discussing the complexities of inviting girls to the ball.
When a little double-twatting round the head with a pair of leather-bound books fails to get the pair concentrating on their work, he sneaks up behind them, rolls up his sleeves and shoves their heads down into their exercise books.
One of the great (and rare) Snape scenes in which he has virtually no dialogue.
Imelda Staunton's Dolores Umbridge took on the coveted position of Defence Against the Dark Arts teacher for Harry's fifth year, and the Ministry official soon makes her presence keenly felt throughout the school, as she gradually works her way towards becoming the acting headmistress.
Despite her pinkly-suited, perma-grinning appearance, she's a terrifying adversary, gradually enforcing ridiculous Ministry rules as she whips the school into line.
Her scariest moment, though, has got to be when she gives Harry lines. Inside her office, which is covered with mewing kitten plates, Harry writes the line 'I must not tell lies' with her inkless quill, and sees the words scratching bloodily into his hand.
Welcome to London
Hagrid takes Harry to London to get him kitted out for his first term at Hogwarts. Instead of taking the lad to WHSmiths to get a pencil case and an unnecessary amount of erasers, they go to Diagon Alley, a cobbled, winding high street for wizards.
From the collapsible brick wall that opens to reveal the bustling street scene, to the goblin-run Gringott's bank, crossing the boundary into the other world captures the wonderment of the franchise perfectly.
Welcome to the Ministry
Harry is summoned to a hearing at the Kafka-esque Ministry after he casts a spell outside of Hogwarts (to repel the Dementors in the underpass). The fifth movie is not as incident-packed as its predecessors, but there's still plenty to marvel at.
Take the set design in the Ministry. Rowling's pages are brought to life within the Orwellian building, where the slick, tiled interior is still underscored with defiantly old-worldy magical touches.
Harry is taken to the hideout for secret wizarding organisation The Order of the Phoenix, and its reveal is as good a moment of reality-sorcery juxtaposition as you'll see in the franchise.
The secret headquarters are unveiled when a posh-looking London terrace magically extends to reveal an extra, hidden lodging. It's a moment that's pure Harry Potter , convincing the audience that the wizarding realm and our own really do co-exist neatly next to one another.
Barty Crouch Jr.
David Tennant has a brief but pivotal role in Goblet of Fire as Death Eater and Voldemort assister Barty Crouch Jr.
In the closing scenes in which he's uncovered as the man behind the series of events that led to Voldemort's rebirth, Tennant brings a big-screen charisma to the slippery, nervy villain that suggests he could have been a massive movie star if he didn't spend the rest of the decade dominating TV screens as Doctor Who.
Voldemort's memory bank
Dumbledore gives Harry a glimpse into the past when he reveals his first encounter with the young Tom Riddle, the boy who would grow up to be Lord Voldemort.
The inky water effect is neatly done, but it's the haunting performance of Hero Fiennes-Tiffin (Ralph's nephew) that'll stick with you. It's also a nice opportunity to get a glimpse of the younger, less-greyly bearded Dumbledore.