Rick and A.J. are in Hawaii tailing a con artist who Jonathan Higgins of the Robin Masters' Estate, has just entrusted with $350,000 in proceeds from his charity event. The three follow her to South America, where they reel her in with a con of their own, using a huge emerald and A.J. as bait.
Story aired as a cross-over with Magnum P.I.; the first half of the story, Ki'i's Don't Lie, aired as a Magnum P.I. episode immediately preceding Emeralds Are Not a Girl's Best Friend.