One hundred million years ago, the central United States was an ocean that was home to some of the largest─and deadliest─aquatic creatures to ever prowl the seas. This National Geographic program takes you on the hunt for these monsters' fossil remains, while computer animation brings long-necked plesiosaurs, giant sea turtles, the 40-foot-long predator tylosaurus, and other amazing beasts to life. Liev Schreiber narrates. 40 min. Widescreen; Soundtracks: English Dolby Digital stereo, Spanish Dolby Digital stereo.