Let's see CHristina's unique BACK TO BASICS TOUR from 2006-2007. The main theme of the concerts were CIRCUS (like in 'Hurt' video)

Than Britney released her album in 2008 with the title Circus, and the Circus tour was a total copy of Christina's BTB Tour... so who copies who? .... Okay it was different, because Britney didn't sing, she lyp-sinched, but CHristina made awesome vocal performances. Hahahaha.

But the tour scene and outfits were totally copied.