'Glee' Britney Spears episode: Harry Shum did a 'double take' with Heather Morris

harry-shum-jr-glee-s2-320.jpgThere might only be one Britney Spears, but "Glee" star Harry Shum, Jr. mistook his co-star Heather Morris for the real thing.

"I'm actually really happy for Heather Morris because this is her breakout episode," Shum tells Zap2it about the "Britney/Brittany" episode airing Tuesday, Sept. 28, in which Cheerios Brittany (Morris) gets gassed at the dentist and imagines herself as Spears in music videos.

"People are going to go nuts when they see her do her thing," he continues. "She looks like Britney in the musical numbers. It's crazy. You have to do a double take. Me and Kevin [McHale] walked into her doing a musical number because some of them we weren't in that she was in. We had heard that Britney was coming on set, so we were like, 'Wait, is that her?' We had to look really closely to see it wasn't."

We've already seen Morris in her "Me Against the Music" outfit, and the latest "Glee" photo shows her dressed as Spears at the MTV Video Music Awards in the skimpy green outfit, complete with a snake as an accessory.

  britney-brittany-glee-heather-morris-snake-500.jpg britney-brittany-heather-morris-02-520.jpg

britney-brittany-heather-morris-03-52.jpg"I'm in some Britney numbers," reveals Shum. "It's insane, if you saw in the previews. They made it look like Britney music videos."

Shum, who's 28, was particularly psyched to do this episode because of the nostalgia and familiarity involved with the song list.

He explains, "You know, some songs on 'Glee' you kind of have heard of but we don't really know the lyrics, so it was really fun to do these songs and not even have to look a the lyrics sheet and be able to know all the songs by heart. It's funny because back in high school when her songs came out, whether you hated her or loved her, you knew her songs by heart. So that was really fun.
 
He falls into the fan category and readily shares his favorite Spears song: "I love 'Toxic.' I think it's a great song."

Check back with Zap2it for more Harry Shum talking about his love triangle, his dancing and of course his abs.

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Photo credit: FOX