Jennifer, who is a judge on the US talent show, turned heads in the revealing sheer and plunging floor-length black dress with multicoloured stripes.
Showing off the red, green, blue and gold detail on the gown, Jennifer posed up a storm backstage for more photos.
The 'Booty' singer finished off her look with shimmering red lipstick, chunky silver earrings and towering black platform heels.
It was a special night on the talent show, as the Top 5 contestants were revealed. After the show, 45-year-old Jennifer was seen leaving a restaurant in Beverly Hills with her ex-boyfriend Casper Smart.
Although having both insisted that they are single in recent interviews, the pair have been spotted out together on numerous occasions in the past month. Jennifer and Casper broke up in June after two years of dating.
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