The Twilight Saga: New Moon (or simply New Moon) is a 2009 American Vampire romantic fantasy film directed by Chris Weitz from a screenplay by Melissa Rosenberg, based on the 2006 novel New Moon by Stephenie Meyer. It is the sequel to Twilight (2008) and the second installment in The Twilight Saga film series. The film stars Kristen Stewart, Robert Pattinson, and Taylor Lautner, reprising their roles as Bella Swan, Edward Cullen, and Jacob Black, respectively. In the film, Bella gets closer with Jacob, who is a werewolf, after Edward leaves her, but when the vampire decides to take a drastic move, she must make a decision between the two.

Summit Entertainment announced it had greenlit the film on November 22, 2008, following the early success of Twilight. Principal photography began on March 23, 2009, in Vancouver, Canada, and ended in Montepulciano, Italy on May 29.

The Twilight Saga: New Moon premiered at the Mann Village Theater in Westwood, California on November 16, 2009, and was theatrically released in the United States on November 20, by Summit Entertainment. The film received generally negative reviews from critics, but grossed $711 million worldwide, becoming the seventh-highest-grossing film of 2009. It set domestic box office records as the biggest midnight opening in the United States and Canada, grossing $26.3 million, which was superseded by its sequel, The Twilight Saga: Eclipse. This led to the highest single-day domestic gross on an opening day, with $72.7 million, until it was beaten by Harry Potter and the Deathly Hallows – Part 2 (2011). The film also became the widest independent release, playing in 4,024 theaters, until it was surpassed by The Twilight Saga: Eclipse. New Moon was released on DVD and Blu-ray on March 20, 2010. As of July 2012, the film has grossed $184.9 million in North American DVD sales, selling more than 8.8 million units, four million of which were sold within its first weekend, beating Twilight's 3.8 million units sold in its first two days.

The film received three sequels, The Twilight Saga: Eclipse, The Twilight Saga: Breaking Dawn – Part 1, and The Twilight Saga: Breaking Dawn – Part 2, in 2010, 2011, and 2012, respectively.

In Forks, Washington, on Bella Swan's eighteenth birthday, she awakens from a dream in which she is an old woman and Edward Cullen, her immortal vampire boyfriend, is forever young.

Edward's family hosts a birthday reception for Bella at their home. After she receives a paper cut and is almost attacked by a bloodthirsty Jasper Cullen, Edward realizes he has put her life in danger by putting her amidst vampires. After rumors start spreading of Carlisle's age and appearance, he ends their relationship and the Cullens leave town.

Bella is left severely depressed and isolates herself for months, during which she has night terrors, enough to push her father, Charlie, to his breaking point where he considered relocating Bella to her mother's place. She accepts a ride from a biker and the dangerous encounter reminds her of a near-assault where Edward rescued her. She realizes that dangerous activities cause her to hallucinate his image. Her Quileute friend Jacob Black supports her during her slump.

While attending a movie with Bella, Jacob abruptly shows signs of pain and leaves. He cuts his long hair and now exhibits the same Quileute tattoo as leader Sam and the other tribe members. He revealed that he knew the Cullens were vampires and inexplicably tells Bella to stay away.