Natural within New York to a Quaker father and Jewish mother, Peet attended Friends Seminary with Liev Schreiber and studied history at Columbia University, where she auditioned for acting teacher Uta Hagen. In the period of her Four-month period of survey by using Hagen, Peet appeared in the off-Broadway revival of Clifford Odets' Awake and Sing.

Her 1st screen performance was the television commercial for Skittles. Her early roles involved the guest starring role in Law & Order, and she made her film debut in 1995, in Animal Room. Peet maintained the steadily acting career within comparatively obscure indie movies. Within one of these, Whipped, she met her todays fellow Brian Van Holt.

Her foremost major role wwhen as "Jack" in the 1999 TV series Jack & Jill which aired for two seasons. Her number one wide-release feature come within 2000, with The Whole Nine Yards, opposite Bruce Willis, elevating her status from supporting actress to lead.

Inside 2000, she was voted one of the Fifty Virtually all Beautiful Humans by People Magazine.

Filmography
Animal Room (1995) Central Park West (1996) (TV series) Winterlude (1996) Virginity (1996) She's the One (1996) Sax and Violins (1997) Grind (1997) Touch Me (1997) Ellen Foster (1997) Origin of the Species (1998) 1999 (1998) Southie (1998) Body Shots (1999) Jack & Jill (1999) (TV Series) Two Ninas (1999) Jump (1999) Simply Irresistible (1999) Playing by Heart (1999) Partners (1999) (TV Series) Isn't She Great (2000) The Whole Nine Yards (2000) Whipped (2000) Saving Silverman (2001) High Crimes (2002) Igby Goes Down (2002) Changing Lanes (2002) Identity (2003) Something's Gotta Give'' (2003) The Whole Ten Yards (2004) Melinda and Melinda (2004) A Lot Like Love (2005) Syriana (2005) The Martian Child (2005) Griffin and Phoenix (2006) Fast Track (2006) Snow Angels (2006)