Doja Cat's Masquerade Ball Birthday Gala Brings Out Big Stars

Doja Cat knows how to make an exclusive Hollywood event feel even more elite -- her 27th birthday brought out a huge list of big names, who were reminded this is as inside as inside gets.

The bash went down Friday night in WeHo at the Raspoutine on Melrose -- and the guest of honor arrived rocking an elaborate gold mask adorned with more feathers than your average peacock.

In fact, almost all her guests showed up in masks -- thankfully, not the kind we had to wear during the pandemic -- adhering to what seems to have been a masquerade ball theme.

Adding to the elite air of the event was Doja's birthday cake -- a massive black and gold covered 3-tiered dessert -- which had several Illuminati logos on it.

Inside, guests partied to a lot of hip hop hits, of course, but we're told there was also a lot of 1950's jazz played too, seemingly a nod to the evening's theme -- and DC joked she wasn't letting her age get her down.

'Cause, as we all know, it's all downhill from 27. 😭

Justin and Hailey Bieber, Kendall Jenner and Shawn Mendes all showed up ready to party -- although it doesn't look like Shawn got the memo on the theme.