Born on Jan. 11, 1972, to mother, Penny, a Jewish social worker and Charles, a corporate lawyer and Quaker, Peet spent her childhood in New York City until her father's career relocated the family to London when she was seven years old. Four years later, they returned to New York where Peet finished high school at the Friends Seminary, a private Quaker school, and went on to attend Columbia University.
Her feature film debut came in 1995 with the movie Animal Room (1995). For a while afterward, Amanda continued to find steady work but also found herself appearing in a depressingly large number of indie films that were never picked up for distribution. She did, however, meet her boyfriend Brian Van Holt on the set of indie movie Whipped (2000). Her turn as the ditzy hit-woman with the heart of gold in the hit comedy The Whole Nine Yards (2000), opposite Bruce Willis, took her from supporting role status to leading lady. That same year she was voted one of the 50 Most Beautiful People in the World by "People" Magazine.
Off-screen, Peet and screenwriter husband David Benioff welcomed a daughter in 2005, and Peet took a break from the business until her appearance as an FBI agent in Chris Carter's second "X-Files" feature, the disappointing second offering, "The X-Files: I Want to Believe" (2008). Peet's second act began more auspiciously than her low budget beginnings, and in 2009 she co-starred with John Cusack in Roland Emmerich's apocalyptic disaster film "2012" (2009). The following year she supported marooned former co-star Jack Black in an adaptation of the classic tale "Gulliver's Travels" (2010), as well as lent her voice to the animated sci-fi adventure, "Quantum Quest: A Cassini Space Odyssey" (2010).