Mol was born in Deep River, Connecticut, where her mother, Janet, is an artist and teacher and her father is a school teacher at RHAM. She went to high school with Broadway actor Peter Lockyer. They performed in school musicals and plays together. Her brother, Jim Mol, is a director and editor in the film industry. Mol attended The American Musical and Dramatic Academy and graduated from the William Esper Studio. After summer stock in Vermont, she took a job for a while as an usher at Angelika Film Center. She was living in a Hell's Kitchen walk-up when she was noticed by a talent agent who spotted her working as a hat check girl at Michael's Restaurant in New York.
In 1998, she appeared in several notable films including Rounders, starring Matt Damon and Woody Allen's Celebrity opposite Leonardo DiCaprio. It was in 1998 that she also came to prominence and notoriety when she was featured on the cover of Vanity Fair magazine. Her appearance was both a triumph and a failure — it brought her great attention, but her movies bombed. Dubbed the "It Girl of the Nineties" by the magazine, her career did not live up to the hype - her early success was not sustained and she faced several lean years before a notable comeback with The Notorious Bettie Page in 2006. While major roles have been sporadic, Mol has been in more than thirty feature films. And though the films have often been small, she has worked for a number of important directors. Her first role came in Spike Lee's 1996 film, Girl 6. She said "I was auditioning for Guiding Light and I was happy I got a Spike Lee movie, which was a tiny part, but all of a sudden I had Spike Lee on my resume. I didn't audition for day player anymore". After Girl 6, New York filmmaker Abel Ferrara took notice and cast her in two movies, The Funeral (1996) and New Rose Hotel (1998). She had a small role in Donnie Brasco (1998). But by now, she was being typecast as "the girlfriend," which she attempted to change by taking a role opposite Jude Law in Music From Another Room (1998), a romantic comedy. Unfortunately, the film went virtually unnoticed by critics and audiences. For her second film with Woody Allen, 1999's Sweet and Lowdown, she played a minor role which the Greenwich Village Gazette called "notable". She played the female lead role in the 1999 film The 13th Floor. She played the victim of a con in the 2003 film, Heavy Put-Away based on the Terry Southern story. In 2006, she shared the lead in a romantic comedy, Puccini for Beginners, in which her character has a lesbian affair. Mol worked with Mary Harron for two years as the director struggled to finance The Notorious Bettie Page: "I kind of felt like I lived with it for a while; certainly not as long as Mary Harron did but I got a good chance to really feel like I knew something about Bettie so by the time the role was mine and I was on set I was pretty confident. I felt like I really worked for it". The next year, 2007, was one of her busiest, with four films in production or in release, including a remake of 3:10 to Yuma starring Russell Crowe, and An American Affair in which her character, Catherine Caswell, has an affair with John F. Kennedy. When released in February 2009, the film was harshly criticized by New York Times critic Stephen Holden, though he said that Mol's part was "quite well acted".
In April 2008, she began filming Tenure in Philadelphia, working opposite Luke Wilson, and Andrew Daly. Though it had received some good reviews after being screened at several film festivals, it was released direct-to-video in February 2010.
|Season 1 credits|
|Boardwalk Empire||The Ivory Tower||Broadway Limited||Anastasia|
|Nights in Ballygran||Family Limitation||Home||Hold Me in Paradise|
|Belle Femme||The Emerald City||Paris Green||A Return to Normalcy|
|Season 2 credits|
|21||Ourselves Alone *||A Dangerous Maid||What Does the Bee Do?|
|Gimcrack & Bunkum||The Age of Reason *||Peg of Old||Two Boats and a Lifeguard|
|Battle of the Century *||Georgia Peaches *||Under God's Power She Flourishes||To the Lost|
|Season 3 credits|
|"Resolution"||"Spaghetti and Coffee" *||"Bone for Tuna"||"Blue Bell Boy" *|
|"You'd Be Surprised"||"Ging Gang Goolie"||"Sunday Best"||"The Pony"|
|"The Milkmaid's Lot"||"A Man, A Plan..."||"Two Imposters"||"Margate Sands"|
|Season four credits|
|"New York Sour"||"Resignation"||"Acres of Diamonds"||"All In"|
|"Erlkonig"||"The North Star"||"William Wilson"||"The Old Ship of Zion"|
|"Marriage and Hunting"||"White Horse Pike"||"Havre De Grace"||"Farewell Daddy Blues"|
* - Credit only, did not appear.