There are three main rumors concerning the plot:
– the Fountain of Youth
– Atlantis (Easter Islands)
– The lost Roanoke Colony
Much more details at: National Treasure 3 in 2010 Nicolas Cage is back as Benjamin Gates
It is reported that Nicolas Cage really appreciated to hang out of the USA for National Treasure 2, so one may bet that he will travel again in National Treasure 3.
It is not yet confirmed if the page 47 of the book of secrets, which Benjamin Gates (Nicolas Cage) described as life-altering, will be part of this new National Treasure movie. Director Jon Turteltaub even hinted that it could actually be the premise of National Treasure 4.
National Treasure 3 is expected to be released in 2010.