Met Gala hosted by Taylor Swift, Idris Elba promises star power

It's a fundraiser at heart but on the outside, the annual Met Gala is one of New York City's most exclusive parties.

A who's who of fashion, music and entertainment will gather Monday to raise money for the Metropolitan Museum of Art's Costume Institute, a collection of 35,000 pieces spanning seven centuries of fashion.

The exclusive guest list is hand-picked by Vogue editor in chief Anna Wintour, and reads a lot like a Forbes list of high earners, mixed with social media's most famous and followed. It puts so many A-listers in the same room that even they themselves couldn't resist breaking the no-selfie rule last year.

For those with the means to attend but not necessarily the brand power, tickets are $25,000 US a head. 

The hosts

Wintour has been the Met Ball's official chair for more than 20 years and each year, she chooses an honorary chair. This year, it's American singer-songwriter Taylor Swift who, along with British actor Idris Elba and Apple's chief design officer, Jonathan Ive, will co-chair the bash.

There's always a major musical guest as well. Last year, it was Rihanna, and Bruno Mars and Kanye West have performed in the past. Swift might not be able to do double duty this year, but there are always others like Beyoncé or Drake to fill those shoes.

The theme

If you're on the red carpet for the Met gala, there's no playing it safe or living in fear of the sartorial police. The occasion is reserved for some of the most creative and outrageous designs, and demands the most confident and fashionably daring to sport them. Check out the looks from last year to see how far they'll go.

This year, the theme is Manus x Machina: Fashion in an age of technology, which is also the inspiration behind the Costume Institute's current exhibition. It's customary that those attending wear outfits that reflect the theme, so expect some futuristic-inspired pieces to interpret the blurred lines between man-made and machine-made fashion.

The guests

The guest list, which includes between 650 and 700 people, is not public, but there are several recurring faces year to year, Jennifer Lopez, Sarah Jessica Parker and Madonna among them. A lot of the guests will spend hours getting ready inside New York's swankiest hotel suites beforehand (and are likely to post their own pre-show preparation on Instagram and Snapchat if you want to follow along).

The point

The high-profile fundraiser marks the official opening of the Costume Institute's annual fashion exhibit, which runs for several months. The benefit gala raised $12 million in 2014 for the institute.

It can also inspire photos that will get a lot of people talking, kind of like the one below of Kim Kardashian and JLo, snapped from behind by Kanye West at this time last year.