When Jay-Z and Kanye West do it big, they do it really big. According to the Evening Standard, the 'Watch the Throne' duo will host a posh shindig in London on Friday to celebrate their joint five-night concert residency at the O2 Arena.

The event will be held at the defunct casino hall Fifty in London's St James’ Street. About 400 guests are expected to attend the bash, including Jay's wife, Beyonce, and West's boo Kim Kardashian. London's top chef Giorgio Locatelli is catering the event, so the food is going to be delish and the Armand de Brignac champagne (aka Ace of Spades) will be flowing in the glasses.

"This is to celebrate the first night of the European tour and they want London to know they’ve arrived," said the source about the lavish get-together. "The place is going to be crazy and they want it to be the party of the year. It will be filled with beautiful women [and] people will be fighting to get inside."

Well, let's hope that doesn't happen.

Along with the food and drinks, Jay-Z is hoping to set up gambling tables so partygoers can try their hand at luck and win some money. "He is looking at getting a temporary casino license for the night so they can set up some of the old tables for guests," said the insider.

Talk about a casino royale.

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