This interlude (I've covered others in posts like this and this [with creepy Jon Voight ((Angelina's dad)) reading a little girl a bed time story and other equally suggestive stuff]) occurs before the 'Freakshow' sex performance. The whole concert pretty much seems to be about slavery, sexual slavery, circus animals and all other themes associated with slavery (if there's a DVD release of it I plan on getting it and doing it as a major Britney post), yet all the fans think it's the "best thing ever!!!!" As an example below, you can skip past the interlude (2:50ish) when an angel in chains flies around (hypnotic voice over the speaker) and Britney comes out (more focused video of this below it) with her masked dancers (along with her own mask of course) and dehumanizing purple tail, more chains, big mirror etc (I posted on these themes before).
MM's one above is very symbolic of the effects of abuse on the mind. Should have included the Eurythmics original video, standard symbolism (one eye, androgyny, masks etc the third eye features pretty prominently).
Edit: Worthwhile responding to a comment I was interested in looking up more info on, looks like (from wiki) Jamie King is the tour director (he choreographed the Britney/Madonna/Xtina "kiss" MTV VMA infamous ritual [directed many of the programmed Mouseketeers Britney, Christina, Justin tours and has worked a lot with Madonna, here is his resume]) and Simon Ellis the musical director (he worked with the Spice Girls [and various other MK'd people/groups ((in the UK anyway)), S Club 7 etc]), William Baker is also involved as a stylist (he did Kylie's X tour; he is often known as 'Kylie's Gay husband', probably one of Kylie's handlers). And the costume designers (all the bondage getup and whatnot) are as fucked up as you'd expect, "The Blonds" (they [assuming the androgynous/transsexual manufactured slave one is actually human] also designed Katy Perry's fruit clothing, some of Rihanna's and such; their myspace page is loaded with all of their symbolic "creations"), "Dsquared" (identical twins) and probably other suspect people. I don't particularly view them as very important, they're all just cogs in the machine churning out the same crap over and over for 'them' (the global 'elite'/ruling class).