Spears is spotted in Beverly Hills after checking out of a Malibu treatment facility earlier in the day. Plus: Angelina & Zahara, Jennifer Aniston and more

2 of 20

'BACK' IN THE SADDLE

After a successful European run, Christina Aguilera rides into Houston for the first stop of her Back to Basics U.S. tour on Tuesday. The pop star's sexy merry-go-round outfit was just one of ten unique costumes designed by Roberto Cavalli that she unveiled during the night's performance.