Britney Spears' birthday party was in full swing Tuesday night, and only ET can take you inside the fabulous circus with all of the celebrity party guests!
Stars such as Lance Bass and Ciara, flocked to New York City's hotspot Tenjune to help the pop sensation celebrate her 27th birthday.
Besides wishing the singer the best on her special night, Lance also had great things to say about Britney's new album.
Watch the video to hear more from Britney's party guests, and be sure to check back on our website for ET's exclusive coverage from the party.
I knew that Ciara would be somehow involved in this when I saw Tierra posting it. You could've just named the thread "Ciara was at Britney's b'day party".
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Ci looked GREAT last night!
jk guh, dont get ghetto on me. 
