All publicity is good publicity, they say, but the royal family is the exception that proves that rule. And recent television coverage of the royals has been – to put it mildly – a mixed bag. The new series of The Crown launched on Netflix within hours of that Prince Andrew interview. One was dependably glorious, which is precisely what royalty is supposed to be. The other was, well, a car crash seems to be the go-to analogy, although I can’t help feeling car crashes are slightly bad-taste imagery when it comes to describing royal PR disasters.

The upshot of all this is that the third series of The Crown will be required to do more heavy lifting than the previous two, in making us fall in love with it – a burden that falls in large part upon the wardrobe department. Clothes, jewellery, hair and makeup are an essential part of The Crown. From the beginning, the series has made the royals more beautiful and more glamorous than their real-life counterparts, and invited us to fall under their spell. The Crown has given the senior royals a newly glittering backstory: here, we see the Queen a spirited young beauty; Prince Philip golden-haired and square-jawed.

But fashion in The Crown does a lot more than sprinkle stardust. Clothes are strategically employed to blur the line between fact and fiction. The third episode of the new series covers the Aberfan tragedy of 1966, which killed 144 people, 116 of them children. Serious and careful, the episode feels almost like a standalone piece. It leans heavily into the Queen’s delay in visiting the village, her absence from the funeral, and subsequent change of heart. The story is imbued with hindsight – you can’t watch it and not be reminded of the Queen’s reluctance to return to London after Diana’s death 31 years later, and how that delay reverberated through British culture and changed so much. But the outfit worn by Olivia Colman is an exact replica of what the Queen wore in 1966: the side-buttoning red coat with a fur trim to pick out the matching hat; the darker brown leather gloves; the handbag. This is more than clothes being used to bring a character to life. This is clothes being used as primary evidence, to make the particular version of the story being told look like the truth.

The Queen visiting Aberfan in 1966 (left); and Olivia Colman wearing a replica of her outfit in The Crown. Composite: Getty/Shutterstock

The puzzles around how much of The Crown “really happened” are a key part of what makes it compelling. In the episode Margaretology, Princess Margaret travels to the White House and singlehandedly saves the British financial system from collapse by weaponising her alcohol tolerance and talent for rude limericks. I precis a little, but you get the gist. Contemporary accounts of the occasion corroborate the evening being a success – the New York Times reported that the after-dinner dancing went on until 2am, during which time “there was laughter and chatting; Margaret smoked a cigarette on a long holder and everyone looked totally at ease”. But The Crown, indulging the 21st-century fascination with soft power and diplomatic dressing, has amplified the importance of this event to feed into its Princess Margaret myth-making.

The zeitgeist works in mysterious ways, and Princess Margaret the style icon is not just a creation of Peter Morgan and The Crown. Her 21st-birthday gown, designed by Christian Dior, had a starring role in the V&A’s blockbusting Dior exhibition this year. Her official portrait wearing the gown, taken by Cecil Beaton, appeared on the cover of a special edition of Harpers Bazaar in February. The cult fashion designer Alessandra Rich, a favourite of everyone from Kate Moss to the Duchess of Cambridge, cites Princess Margaret as one of her muses. But by riffing not only on her glamour but also on her political acumen, The Crown brings echoes of Hilary Mantel’s Thomas Cromwell into her on-screen character. There is a mightiness to her party entrances, sweeping into a room like a galleon in full sail, which would do as well for Wolf Hall as Buck House.

The real royals arrive for the investiture of Prince Charles in 1969 (left); and the Queen Mother and Princess Margaret in The Crown. Composite: Getty/Des Willie/Netflix

But most of all, Helena Bonham Carter’s version of Margaret is the royal family’s Elizabeth Taylor – a reference that presages the marital dramas to play out later in this time period. The series’ very first shot of her shows a hefty diamond bracelet as a naked arm stretches out of tangled sheets to answer a ringing phone. The second sees her in a floaty, kaftan-style robe, marching across cobbled streets to pick a fight with her beloved. Diamonds, kaftans and lovers’ tiffs: this is as Taylor as it gets. Where Vanessa Kirby’s younger Margaret was delicate and damaged, Bonham Carter brings a Burton-esque exaggeration. She is always either roaring with laughter, the pearls at her throat catching the light as she throws back her head, or she is face-down in a two-day hangover. Her wardobe, like the Queen’s, is in many instances a carbon copy of real life – for instance, her pink suit at Prince Charles’s investiture is reproduced, along with the matching outsize pink hair bow which, as it happens, is very on trend for this season. But elsewhere, her looks – sunglasses, cigarette holders, winged eyeliner, a startling pair of floral-printed stilettos, off-the-shoulder dresses that recall Taylor in Giant – are every inch the movie-star princess.

The Queen with Prince Philip in The Crown. Photograph: Des Willie/Courtesy of Des Willie/Netflix

The contrast with her older sister the Queen is exaggerated for comic visual effect: after Margaret has begun her day in diamonds and a kaftan, with a fag and a row, we see the Queen at her breakfast table in a skirt suit, taking her bottled-up emotions out on the butter knife as it rasps a tiny sliver of marmalade across crustless toast. She draws attention to her pearls not when she throws her head back in laughter, but when she clutches her hands to them anxiously, rolling them across her clavicles like worry beads.

There are echoes in this show with the other programme everyone watched on television recently, Succession. The Rolls-Royce Phantom has swapped in for the yacht, the Bakelite phone in a white gloved hand for the constantly pinging email, but there are the same dysfunctionalities and similarly ludicrous real estate. The Crown exercises artistic licence to make the characters more glamorous, more often than it does to make them more sympathetic, because – as in Succession – it is the character flaws that drive the story. The clothes are there to win our votes, even when the characters don’t deserve them. As Harold Wilson says to the Queen, early in this series: “Everything is political.” And some things really don’t change.