2013 Grammy Awards: what to watch for when stars hit the stage (VIDEO)

Tonight’s 55th annual Grammy Awards promises 3 ½ hours of musical mayhem.

Expect performances from Taylor Swift, Frank Ocean, Mumford & Sons, fun., and Carrie Underwood, among others.

The show begins at 8 p.m. Eastern time from the Staples Center in Los Angeles with CBS handling the broadcast duties.

Here are some moments to watch for.

1. Rihanna’s salute to Bob Marley
Rihanna is a well-known Marley lover, and will appear with Sting, Bruno Mars and a collection of the Jamaican musical pioneer’s family members on stage.

Using Twitter and Instagram, Rihanna whet appetites by releasing a photo of her standing with Marley’s descendants.

This probably would’ve helped everyone forget that three years ago boyfriend Chris Brown landed himself an assault charge for hitting Rihanna on Grammy weekend.

Too bad Brown crashed his car on Saturday night fleeing paparazzi, then appeared later at a pre-Grammy party hugging the “Umbrella” star.

Guess we’ll just have to watch for fireworks.

2. Taylor Swift’s opening act
Since Swift is performing first it promises to be the biggest spectacle of the night, which you’d hope since she had the audacity to campaign for her place in the lineup.

She told Ryan Seacrest's radio show that her people approached the show’s producers, who agreed she should sing.

“And then like a week ago they call us and are like, ‘Oh, by the way, you’re opening the show.’ It’s not like they approach you…It just surprised me I was going to go first,” she told the "American Idol" host.

That comes off as a touch cheeky to us, but maybe her ideas were just so good she had to share them.

Swift wouldn’t reveal exactly what song won over the Grammy gurus, but suggested that since she’s nominated for “We Are Never Ever Getting Together,” that it might make the cut.

3. T & A
T and A, did we just write that? Sorry to be so crude, but you have to wonder what CBS was thinking when it issued a “wardrobe warning.”

Apparently sensitive to potential malfunctions, side boob and thong songs, the American network asked stars to cover up their special areas.

“Please be sure that buttocks and female breasts are adequately covered,” a CBS advisory said. “Please avoid exposing bare fleshy under curves of the buttocks and buttock crack. Bare sides or under curvature of the breasts is also problematic.”

Something tells us you should expect at least one superstar to take this as a challenge, and let loose tonight with one or two “fleshy under curves” especially for the cameras.

Why? Just because they’re musicians and this is what they do.

4. Frank Ocean rides the wave
He wowed us on “Saturday Night Live” this season with his superior musical chops, and he’s endearing as one of the few (only?) openly gay R&B artists.

We’re not getting into his sexuality here because really it doesn’t matter, and his music is just too darn good to diminish with such talk.

Really, he just deserves to win an arm-load of trophies. Not to mention he was involved with the aforementioned Chris Brown in a parking lot scuffle earlier this year, and anyone who fights Brown is OK in our books.

“So it’s officially Grammy weekend, which is probably not a big deal for everyone,” he told the crowd at another pre-awards party where he was singing, “but it makes me nervous as f—.”

He’s in tough, though. Mumford & Sons, fun., Jay-Z, Kanye West and Dan Auerbach of the Black Keys also have six nominations each.

5. Carly Rae Jepsen recruits Newtown kids
Really, this isn’t fair. We don’t like crying during TV shows, but how can you expect us to remain composed when this collaboration hits the airwaves?

The Sandy Hook Elementary School Chorus is to sing Jepsen’s hit during the “Live from the Red Carpet” preshow, so you’ll have to find the E! Network to watch.

Trust us that it’s worth the effort, we’re still recovering emotionally from the students’ performance of “America the Beautiful” at this year’s Super Bowl.

“This opportunity to do something positive lets the kids know that although a lot of things happen in our world that are not pleasant … there are many giving people and wonderful things that can come out of life, so don't get discouraged,” chorus director Sabrina Post said.