I got a sneak peek at a diva-licious 'Glee' number today -- the show's 300th performance -- and can share some spoilery details with you here, if you're curious.

And 'Glee' fans, I know you're curious.

Take a peek after the jump to see what Mercedes, Santana and another soon-to-be-ex-New Directions member are up to for the big number, which we won't see until the Nov. 15 episode...

The student body of McKinley High School keeps on growing. 'American Dreams' actress Vanessa Lengies has booked a recurring role on 'Glee.'

According to TVLine, Lengies will play Sugar, a new student who can't carry a tune. Lengies joins 'Friday Night Lights' and 'Cougar Town' actor LaMarcus Tinker as new recurring players on the hit Fox show. Tinker will play the new love interest for Amber Riley's Mercedes character.

Lengies currently plays Kelly Epson on TNT's 'HawthoRNe.'

In other casting news ...

The former 90210 and Freddie star will play the gay half of a writing team in a new sitcom from David Kohan and Max Mutchnick, the writing team that brought us Will & Grace. The show will be sorta based on their lives together, a writing team where one guy is straight and one guy is gay. Also cast are Jessica Capshaw and Vanessa Lengies. No word yet on who will play the straight half of the team.

I never watched 90210, so I have no idea what Greene was like on that show (though I do remember him as a kid on Knot's Landing). I do know that he was the best thing about Freddie, playing the horny, always scheming best friend of the Freddie Prinze, Jr. character, so this could be interesting.