Ryan Dunn

By DAILY MAIL REPORTER

Britney appearance: The pop princess and actress Heather Morris act out Me Against The Music video

Britney's much trumpeted appearance on show Glee has yet to be screened.

But a new promo of the cast performing her song Me Against The Music shows she may have competition from cast member Heather Morris who performs her hit song.

Dressed in a black suit with a matching trilby Heather looked uncannily like the pop star as she gyrated her way through her dance routine.

Scroll down to watch the videos....

Dancing queen: Morris was a former backing dancer for Beyonce - and it shows in her sharp performance

Sneak peek: Heather stars in the episode which will be screened in the U.S on Tuesday night, alongside new cast member John Stamos

The episode doesn't air in the U.S until Tuesday night.

But excitement over the much-anticipated episode is building after the release of a new preview.

This is the second look viewers have been given - and it looks like Britney fans will not be disappointed.

It's Heather....: Britney has said she is really excited to see the show which will use six of her songs

In the first preview Fox released, viewers get a brief sneak peek at each of the six Spears songs that are used in the show.

These include: Hit Me Baby (One More Time), Oops I Did It Again, Stronger, Slave For You, Toxic and Me Against The Music.

in the second preview, we get more footage of the Me Against the Music number, featuring John Stamos.

Ooops I did it again: A new promo video has been released for the Britney Spears themed episode of the show

While filming the episode Britney uploaded pictures of herself on the set to her Twitter social networking page with the message: 'What's up GLEEKS? Having so much fun on set!!

'Can't wait for you guys to see the episode!'

The episode showcases the singing and dancing talents of Heather Morris, who pays Brittany in the Emmy-winning show.

Morris was originally brought in as a trainer to teach the Single Ladies dance to Chris Colfer and Jenna Ushkowitz, having previously been a backing dancer for Beyonce.

When the show's producers saw her they offered her the role of Brittany, the show's resident cheerleader.

The synopsis of the show reveals that Brittany and the crew try to persuade Mr Schuester to do a Britney Spears-themed number, but he is reluctant as he deems her 'too edgy.'

Scene stealer: Heather Morris looks uncannily like Britney as she performs the pop star's song Me Against The Music

Hit show: Last night's season two premiere pulled in over 12 million viewers

Meanwhile a insecure Will is curious about Emma’s new beau, Dr. Carl Howell, so he convinces her to bring him in to talk to the kids about dental hygiene.

While the dreamy doc inspires the girls to take their dental health more seriously, Will is left feeling worse than before.

Last night's season two Glee premiere pulled in 12.3 million viewers - a 20 per cent increase from the shows first season premiere, and the Britney Spears episode is likely to attract even more.