'Pirates of the Caribbean: On Stranger Tides' has sailed across the $1 billion mark at the worldwide box office, and the blockbuster hit arrives on 3D Blu-ray and DVD on October 18. In anticipation, we have an exclusive look at bonus features detailing the film’s mermaid magic!In 'Pirates of the Caribbean: On Stranger Tides,' exotic and deadly mermaids play a key role in Jack Sparrow's (Johnny Depp) search for the Fountain of Youth along with Blackbeard's daughter (Penelope Cruz). Behind the scenes, mega-producer Jerry Bruckheimer and director Rob Marshall enlisted three sets of mermaids, including Olympic, stunt and synchronized swimmers to portray the grace and fury of the undersea sirens. (ETonline.com)