Glee Sneak Peek: Go Behind the Scenes of Rachel and Cassandra's "Jazz"-Off

Ever since Rachel (Lea Michele) first set foot in Cassandra July's NYADA dance class on Glee, the two have been at odds. About Cassandra's teaching style. Her unusual drinking habits. Her career. And most recently, about Brody (Dean Geyer).

So how are these two talented and headstrong women supposed to settle their beef? A sing-off? Nope! A dance-off!

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In this sneak peek from Thursday's new episode (9/8c on Fox), Cassandra (Kate Hudson) challenges the plucky ingénue to a dance-off set to the tune of Chicago's "All That Jazz."  "In this episode, Rachel starts to become a little bit more defiant and sure of herself in class," Hudson explains, "and we end up in a little dance-off."

This is hardly Glee's first time visiting the long-running musical's songbook. Back in Season 2, Rachel got in the flapper-spirit with substitute Holly Holliday for an impressive performance of "Nowadays/ Hot Honey Rag". In Season 3, several of New Directions' female members, including Santana and Mercedes, performed the "Cell Block Tango" when the ladies were assigned to sing a song about women feeling weak because of men.

Watch Hudson share her personal connection to the long-running musical and see how this latest Chicago number ranks:

Who do you think will win the dance-off? Will Rachel and Cassandra ever learn to get along?

Glee airs Thursdays at 9/8c on Fox.