From AC360.com a "web exclusive" ~
Was American hostage Bob Levinson captured while on a secret mission?
In 2007, it's believed Bob Levinson was taken hostage while traveling in Iran. He has now been held captive overseas longer than any other American. There is evidence suggesting Levinson may have been a spy and working with people inside the CIA who had no business staging operations. Anderson discussed all of this with "Blowback" author Valerie Plame and Bob Baer. Both are former CIA officers.