Julianne Hough in a Bikini

Julianne Hough is looking very '80s here -- on purpose. This neon purple bikini is from the 'Rock of Ages' movie she starred in, playing as Sherrie Christian in 2012. The movie was set in the time of hair bands and high waistlines, but this singer is still smokin', even retro. When you dedicate your life to dance, you tend to have a little muscle tone. Hough would look great in any decade.

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