Robert Pattinson, Kristen Stewart and Taylor Lautner shed some light on the finer plot nuances of “Breaking Dawn, Part 1,” including Bella’s secret apprehension about marrying vampire lover Edward Cullen.

The cast members spoke in a new interview with “Entertainment Tonight,” as part of the promotion for the upcoming movie, which hits theaters next month.

“Bella is absolutely certain that she wants to spend forever with Edward, but there is just something about marriage that she’s apprehensive about,” Kristen explains.

Rob, Kristen Twilight Embrace
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“It comes from the way she was brought up,” she adds.

The apprehensive is evidence just before the wedding, Kristen reveals. “There are a few looks from Edward that are just unclear to her,” she says.

The vampire human couple also have mixed emotions about the baby. Bella wants it and Edward is really terrified of it. And with good reason.

The half-vampire, half-human baby almost costs Bella her life and leads to her becoming a vampire herself.

Rob talks about the relationship between Edward and Jacob, and how it can never be totally whole. Neither really want a friendship, he says.

They are eventually forced to live together and eventually bond, because they both want the same thing for Bella.

Taylor talks about how Jacob changes from being jealous, hot-headed and still into Bella in the beginning of the movie to someone who matures throughout the movie.

The movie opens with the wedded bliss of Bella and Edward. But it’s cut short by a series of betrayals and misfortunes.

Their night of passion on their honeymoon in Rio de Janeiro leads to Bella’s pregnancy and near fatal childbirth.

Edward finally forced to fulfill her wish to become immortal.

But daughter, Renesmee, pits the Cullens and their allies against the fearsome Volturi, leading to an all-out battle.

Check out the interview below and start counting the days until the movie debuts.