Julianne Hough strikes a pose with gal pal Audrey as they celebrate their good friend Janelle‘s birthday at a masquerade party on Saturday night (January 9) in Los Angeles.

The 21-year-old singer/dancer/actress was spotted at Trashy Lingerie boutique in West Hollywood earlier in the day, picking up a feathery mask to complete her costume. Julianne described her costume as: “I look like cat woman/bird/Michelle Phfifer [sic]/Olivia Newton-John.”

While Julianne was celebrating her friend’s birthday, costar Christina Aguilera was busy filming Burlesque.

20+ pics inside of Julianne Hough…