'Glee' does 'Britney 2.0' - 5 things to expect from the Britney Spears tribute

Don't worry, the "Glee" powers that be know it seems strange to pay tribute to Britney Spears again, considering they did a pretty thorough job in Season 3. But the episode, which focuses on the meltdown of everyone's favorite dumb-as-a-rock Cheerio, Brittany (Heather Morris), totally makes sense -- and is hilarious to boot.

Zap2it screened the episode early at the "Glee" Season 4 premiere, and we can attest that it does not go easy on the newly minted "X Factor" judge. In fact, because there's an actual plot and no dentist-induced dream sequences, it might be the best tribute episode since the Season 1 Madonna outing.

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Here are five things to expect from "Britney 2.0":

1. Britney might not have been as happy about her "Glee" tribute this time around, since it focuses mainly on her meltdown. Brit might be a new member of the FOX family, but that doesn't mean "Glee" went easy on her. Morris does some of her funniest work as the head-shaving, umbrella-wielding, Cheeto-eating Britney we all feared for a few years ago.

2. We'll see not one but two McKinley High graduates that weren't in the premiere. They're not gratuitously shoehorned in cameos, either -- both appearances are completely natural in terms of the episode's plot. (If you think pretty hard, you'll likely be able to guess who they are, too. But we're not telling.)

3. Tina, Sam and Joe will perform the best version of Britney's "3" you've ever heard. Including Britney's. It's a stripped-down, acoustic take on the dance tune, and we can't wait to buy it on iTunes and listen to it 50 times in a row.

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4. Marley and Jake sing the first romantic duet of Season 4. But that doesn't mean the couple creator Ryan Murphy has already dubbed "Jarley" will actually get together so soon. This is a teen drama, people -- there will clearly be obstacles in the way of their eventual (and likely short-lived) happiness.

5. Kate Hudson is a freak of nature. We've already seen her impossibly flat stomach, and during a heart-to-heart in the dance studio with Rachel we'll see her insane flexibility at work. Reminder: girlfriend has had two children. It's really not fair.

"Britney 2.0" airs Thursday, Sept. 20 at 9 p.m. on FOX. Are you excited for the second Britney tribute?