Britney Spears' "Glee" Episode Hits Ratings High

NEW YORK (CBS) "Glee" earned its highest ratings ever on Tuesday night with its much-anticipated tribute to Britney Spears.

The Fox series drew 13.3 million viewers for the episode, earning a 5.8 rating among adults ages 18-49. That's the highest rating the show has ever received - even bigger than last year's Madonna-themed episode.

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According to Entertainment Weekly, the network announced that this is the first time in 17 years that the highest-rated entertainment program of premiere week actually grew in week two among adults in that coveted age bracket and among total viewers (the last time was in the Fall of 1993 with "Seinfeld").

Each rating point represents 1.31 million viewers.

The episode featured five Spears songs and three short cameos from the pop diva herself. The glee club students experienced fantasies in which they performed the hits while under anesthesia at the dentist's  (played by guest star John Stamos) office.