Imagine if WB decided to make a Harry Potter series set in the present day, with the characters as their adult selves.

As of 2021, Harry and Co would be just over 40 years old, though you could have some wiggle room around that age range because (i) make up can do a lot and (ii) you can always say wizards age differently.

Who do you cast?

Some ideas:

Harry Potter: Tom Hardy

Hermione Granger: Gemma Arterton OR Felicity Jones

Ron Weasley: Simon Pegg

Ginny Weasley: Karen Gillan

Luna Lovegood: Rosamund Pike

Neville Longbottom: Martin Freeman

Fleur Delacour: Léa Seydoux

 

Fleur: Pom Klementieff

Harry: Ben Barnes

Luna: Emily Kinney

Ginny: Charlotte Hope

Hermione: Emily Blunt or Phoebe Waller-Bridge

Ron: Taron Edgerton

Neville: Andrew Scott

 

Harry: Joseph Gordon Levitt
Ron: Simon Pegg Seth Green Works better
Hermione: Charlize Theron

Neville: Henry cavill

 

This is my pick without joking about it.

I tried to keep them 40 years old or older since the original actors are 30 years old, but Luna is hard to pick and my choice is only 34 years old.

Harry: Jake Gyllenhaal (40)

Ron: Seth Green (47)

Hermione: Natalie Portman (39)

Ginny: Amy Adams (46)

Draco: Boyd Holbrook (40)

Luna: Pom Klementieff (34)

Neville: Henry Cavill (37)

Fleur: Katheryn Winnick (43)

EDIT:
And to add something more to discussion than just a list, I like Karen Gillan choice as Ginny. Her Amy in Doctor Who has an energy and attitude that would work with this character.

Léa Seydoux for Fleur is a good choice too and she has bonus points for being French.

Twice Simon Pegg for Ron, but can't say I'm convinced. He plays a very good funny sidekicks, but he doesn't work for me as this character.

 

@Celestin I agree. Seth green works better.

Also, I'm one hundred percent imagining a scen where the trio says, "We need to talk wit hNeville about this"

They head to the greenhouse and the room is filled with lovestruck female students making eyes at the "hot professor."

 

Out of curiosity, what's the reasoning behind this one? In real life, Hardy comes off as prickly and reclusive. In his roles, I've only seen him project two auras: silent and handsome; and then silent and handsome with a dose of simmering, explosive rage. His natural expression is a scowl.

I'd cast him as a Death Eater, or maybe the stone-faced bouncer in a seedy, Knockturn bar. Maybe I haven't seen enough Tom Hardy films.

 

Hermione: Hayley Atwell or Anna Friel.

Draco: Dan Stevens

Harry: Aaron Taylor Johnson

Ron: Arthur Darvill

 

This obviously isn't an all British cast like Rowling originally wanted - but I tried to capture some of Rowling's descriptions, and tried to imagine how they'd look like given their profession, etc.

Harry: Sebastian Stan

Ginny: Brittany Snow

Ron: Ed Sheeran Domhnall Gleeson (I really liked him in About Time, and I thought he gave off those Adult Ron vibes)

Hermione: Jenny Slate

Draco: Dan Stevens

Neville: Paul Rudd

Luna: Amanda Seyfried

 

I mean, he was Bill.

 

Yeah but Bill had like 5 minutes of movie time. It's honestly like he wasn't even there.

 

Hmm. I'm not sure that one would work. Paul Rudd is like the comic relief guy for reality. I only need to see the guy's face and I'm already halfway snickering. I just don't think he could pull off the competent, serious and self-assured forty-something I always pictured Neville becoming - without somehow turning it into a joke, anyway.

But I do think that Amanda Seyfried would make a fantastic adult Luna.

 

You know what you’re right. I’m actually going to go with Harry Hadden-Paton instead. Still matches the image in my mind

 

Harry: Dominic Cooper
Ron : Ewan Brenmer if a comedy take, Damien Lewis if he's supposed to be cool
Neville (who should be a bit round and sandy-haired): Nick Frost

Edit for inspiration:
Hermione: Billie Piper

 

Harry: Richard Ayoade
Ron: Noel Fielding
Hermione: Susie Dent
Luna: Rachel Riley
Ginny: Roisin Conaty
Malfoy: Jimmy Carr idk

Call it "8 out of 10 Cats Does Hogwarts"

 

Pansy: Katherine Ryan
Neville: Lee Mack
Goyle: Rhod Gilbert
Molly: Sarah Millican

Man, this is the best idea I've heard in a while. Just give all the regulars on the show the scripts and their drinks of choice, and let them go. I'd actually pay money to see this.

 

I don't really have objections to a lot of these, so I think I'd say something for a few specific ones only (assuming I can pick non-UK actors):
Luna: Amanda Seyfried
Ginny: Karen Gillan
Lavender: Scarlett Johansson
Parvati: Janina Gavankar
Fleur: Mélanie Laurent

I think Richard Ayoade could also play every male role honestly, just get him different specs for each character to differentiate them.

 

Harry Potter: Hugh Dancy (45)
Ron Weasley: Damian Lewis (50)
Hermione Granger: Anna Friel (44)
Ginny Weasley: Sienna Miller (39)
Luna Lovegood: Joanne Froggatt (40)
Neville Longbottom: Nick Frost (48)
Fleur Delacour: Frédérique Bel (45)

I tried to keep to British actors like JKR did originally (with a French actress for Fleur). Hugh's been my face claim for adult Harry for a number of years now. Pretty much since Hannibal.

 

Ron : Tim Key