the story of the movie :
The new found married bliss of Bella Swan and vampire Edward Cullen is cut short when a series of betrayals and misfortunes threatens to destroy their world. Bella soon discovers she is pregnant, and during a nearly fatal childbirth, Edward finally fulfills her wish to become immortal. But the arrival of their remarkable daughter, Renesmee, sets in motion a perilous chain of events that pits the Cullens and their allies against the Volturi, the fearsome council of vampire leaders, setting the stage for an all-out battle