Image copyright Reuters

The Met Gala, an annual benefit event for the Costume Institute at the Metropolitan Museum of Art in New York, is considered one of the world's biggest fashion events.

It is known for its exclusive guest list, its expensive tickets and - most of all - its extravagant outfits, based on a different theme each year.

This year, that theme was Camp: Notes on Fashion - to coincide with an upcoming exhibition at the Met, inspired by US writer and political activist Susan Sontag's 1964 essay, Notes on Camp.

The outfits this year were therefore, like the exhibition, based on "irony, humour, parody, pastiche, artifice, theatricality and exaggeration".

And showing everyone how it was done at the very start of the night was singer Lady Gaga, who arrived in a billowing pink outfit which was not quite what it seemed at first glance.

Image copyright AFP Image caption Lady Gaga, one of the event's co-hosts, arrived in a billowing pink outfit...

Image copyright AFP Image caption Which opened up to reveal a black gown, her second outfit...

Image copyright Getty Images Image caption Which was then cast aside in favour of Lady Gaga's third outfit, a slim-fitting pink gown

Image copyright Getty Images Image caption ...Which she then took off, to reveal her final outfit

Image copyright Getty Images Image caption Serena Williams, who is also co-hosting, arrived in a neon yellow gown - with matching Nike trainers

Image copyright Getty Images Image caption Singer Janelle Monae turned heads in a gown complete with a blinking eye

Image copyright Reuters Image caption Kenyan actress Lupita Nyong'o smiles for the camera

Image copyright Getty Images Image caption Actor Michael Urie has gone for two looks in one

Image copyright Reuters Image caption Actor Ezra Miller shows off some very impressive (and unsettling) make-up art

Image copyright Reuters Image caption Katy Perry is dressed as a chandelier

Image copyright Reuters Image caption Reality TV family the Kardashians were out in force for this year's event

Image copyright Getty Images Image caption Here are newlyweds Priyanka Chopra and Nick Jonas, who are said to have first met at the Met Gala in 2017

Image copyright AFP Image caption They were followed down the red carpet by Nick's older brother Joe and his even newer wife, Game of Thrones star Sophie Turner

Image copyright Getty Images Image caption Bollywood star Deepika Padukone channelled Barbie in a large pink gown

Image copyright AFP Image caption Laverne Cox went for a sleek black dress and bold make up

Image copyright Reuters Image caption The third co-host is Harry Styles, who wore a sheer black top and high-waisted trousers

Image copyright Reuters Image caption Alessandro Michele, of Gucci fashion house, is the event's final co-host

Image caption Singer Billy Porter made an entrance before flexing his wings in front of the crowds

Image copyright Getty Images Image caption And theatre owner Jordan Roth has, very aptly, turned himself into a theatre hall

Image copyright Getty Images Image caption Celine Dion, perhaps the original queen of 'camp', did not disappoint

Image copyright Getty Images Image caption Actor Jared Leto clearly believes that two heads are better than one

Image copyright AFP Image caption US drag queen Aquaria went for painted hair and diamante hand-pieces

Image copyright AFP Image caption While actor Yara Shahidi has gone all out with the feathers...

Image copyright EPA Image caption ...Much like the Met Gala's main host, Vogue editor Anna Wintour

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