Justin Bieber, Selena Gomez Rock Billboard Music Awards White Carpet

You know you’re in for an interesting night when Justin Bieber arrives in a gold blazer, and last night’s Billboard Music Awards proved to be exactly that. From surprising duets to unexpected cameos (it's Britney, bitch!), the ceremony had plenty of awesome moments, but what really caught our attention was the red carpet fashion. The guys and gals, including Selena Gomez, Rihanna and more, wore outfits ranging from totally glam to slightly absurd. We highlight some of the more noteworthy looks below.

If Justin's goal last night was to shock us (or is it wow us? We're not sure yet!), he definitely succeeded. The Biebs hit the red carpet in a gold blazer (with SHIMMER) and a black tie that totally had us doing a double-take. Admittedly, we kinda prefer Justin in black-on-black, but we can't blame the guy for stepping things up a notch. After all, he did have to hold his own next to girlfriend (did you see that smooch they shared?!) Selena, who looked totally fab in a black Dolce&Gabbana gown with cut-outs at the waist. Sel paired the chic gown with some striking red heels and wore her hair flat-iron straight (great choice!).

We were literally giddy with excitement when Brit made a surprise appearance at the end of Rihanna's opening performance of "S&M" (we can't help it, we love the girl), and while she wore a slightly risque leotard onstage, her off-stage look was much more demure. Britney (who has certainly made some interesting fashion choices in the past), looked great in a sleek, black mini-dress that she paired with some criss-cross heels. While Britney wore all black, Rihanna went the complete opposite route. RiRi arrived at the show in an all-white outfit, including a blazer and loose trousers, by Max Azria. The girl looked amazing in the white ensemble, which stood out especially because of her fiery-red hair. We can't help but wonder, though, if this ensemble would have been better suited for a night out in St. Tropez (or some other amazing island we wish we could fly away to) than this awards show.

Let's face it, everyone wants to look good when their ex is in the building, so it's little wonder that both Taylor Swift and her old beau Joe Jonas were fashion hits last night. Taylor looked every bit the classic beauty in a sparkly, strapless nude gown by Elie Saab (that sorta reminded us of Ashley Greene's Costume Institute Gala gown), while Joe arrived in a black suit (with quarter-sleeves!) and some killer white sneakers. Also, can we take a moment to appreciate Joe's buzz cut? So grown up.

Click on any of the images above to see our entire Billboard Music Awards fashion flipbook!

What did you think about the looks at last night's event? Tell us in the comments and on Twitter!