Long accustomed to being top of the class, Hermione Granger had to concede Harry had the edge when it came to Defence Against the Dark Arts. Unquestionably, nobody but he could have taught his comrades the Patronus Charm with such skill, authority and experience.

Plus, Harry’s almost talismanic quality as The Boy Who Lived lent their risky enterprise a magic power beyond that of any spell.

But in every other important respect Hermione was the key player. She took initiative when appropriate, inspired others when spirits were down – and was ruthless when it came to the crunch. Without Hermione’s skills, Dumbledore’s Army would’ve been more like Dumbledore’s Bunch of Kids Standing Around Not Quite Knowing What To Do.

A shrewd mind

The very inception of Dumbledore’s Army can be traced to Hermione’s intellectual outrage. Dolores Umbridge, new in post as Defence Against the Dark Arts teacher, tried to fob the class off with a theory-only syllabus. Never usually one to question her teachers – and certainly not afraid of book learning – Hermione nonetheless stood up for the principle that without practical spell-casting the lesson was useless.

Eager to muster resistance, yet aware she couldn’t do it alone, she worked hard to convince a reluctant Harry to lead an army. That required time, patience and more than just book smarts…

Slick manoeuvring

Using her own initiative, Hermione invited fellow students to a meeting at the Hog’s Head, with an eye to recruiting them for the as-yet unnamed army. Disingenuously, she told still-sceptical Harry that she’d only invited ‘a couple of people’ to attend, and that they shouldn’t worry about being overheard by malevolent forces (when she really had no basis for that). By the time a small crowd of students rocked up it was too late for Harry to back out. Smooth.

A silver tongue

While there was never any doubt Harry was the linchpin of the group, Hermione herself took the lead and called the meeting to order. At first hesitantly, but with growing confidence, she outlined her objectives. Harry, suspicious that the group was only there for lurid gossip about the death of Cedric Diggory, also required delicate handling. Naturally, she bossed it.

And masterfully, having set the wheels in motion, Hermione backed off at the perfect moment, allowing conversation to turn to Harry’s considerable credentials – slaying the Basilisk, winning the Triwizard Tournament, and so on. With deft political instincts, the moment the meeting began to turn fractious, she butted in to close the matter: ‘…moving on… the point is, are we agreed we want to take lessons from Harry?’

Magical admin

Having campaigned effectively, and got her fellow students to all sign up, Hermione was next confronted with the dry logistics that lie at the core of any complex organisation. Basic schedule clashes – classes, Quidditch practice – all threatened to crush Dumbledore’s Army before it even started. So she hit upon the inspired idea of bewitching coins with the Protean Charm, handing them to her fellow conspirators as nifty under-the-radar communication devices. Problem solved.

Hardcore hexing

Controversially, she also hexed the very sign-up sheet her fellow students used to indicate their loyalty, and poor Marietta Edgecombe paid the price in pustules. Marietta still snitched, of course, but we’ll never know how much difference that actually made – and it’s probably fair to say that if anyone else was thinking of snitching, they very quickly changed their minds.

Handy in a scrap

Hermione took on Bellatrix Lestrange – with the Death Eater’s own wand. And defeated several other opponents too. Make no mistake – this girl is no pushover.

Without Hermione Granger’s brains, tactical nous, eloquence, dexterity and devastating use of force, Dumbledore’s Army would have sunk. If, indeed, it ever would have existed at all.