A familiar face to the teen set through her work on the popular series and her numerous magazine covers, Biel was cast opposite heartthrob Jonathan Taylor Thomas in the 1998 holiday film "I'll Be Home For Christmas", playing his well-grounded and assertive girlfriend Allie. Her first film role was in "Ulee's Gold" (1997), starring Peter Fonda, in which she played Fonda's troubled granddaughter Casey, a departure from her "7th Heaven" role.

The taught, toned Biel raised eyebrows when she posed semi-nude for a cover and photo layout for Gear magazine as a teen in an attempt to shed her wholesome image and, possibly, be released from her TV contract. She ultimately negotiated a reduced, recurring role on the series and branched further into features, playing Freddie Prinze Jr.'s fantasy rich girl and adding a bit of sexy zest to the otherwise dreary baseball comedy "Summer Catch." She next took on her edgiest projects yet, appearing as promiscuous college student Lara Halleran in writer-director Roger Avary's blunt, sex-soaked adaptation of Brett Easton Ellis' novel "The Rules of Attraction" (2002) and as Erin, the central scream queen of the hit 2003 remake of "The Texas Chainsaw Massacre."

In “Cellular” (2004), Biel played the spurned romantic interest of a man (Chris Evans) who gets thrown into a high-stakes chase after receiving a random call on his cell phone. Thankfully, her small part in this forgettable action-thriller went virtually unnoticed, with no harm done to her career. Meanwhile, the young actress appeared in “Blade: Trinity” (2004), the third installment in the popular B-movie franchise. Biel played Abigail Whistler, leader of a group of human vampire hunters who team up with Blade (Wesley Snipes) to do battle with Dracula and his gang of undead thugs. Early reviews indicated that the flick was for fans only: a videogame plot, loud soundtrack, and ADD-induced editing might turn off mainstream audiences. Biel's next effort was "Stealth" (2005), a stupefyingly lowbrow cross between "Top Gun" and "2001" as a female fighter pilot of a new generation stealth plane who also manages to slip into a bikini for the film. A much better career move was a smaller supporting role in writer-director Cameron Crowe's romantic comedy "Elizabethtown" (2005), as the beautiful girlfriend of a whiz-kid athletic shoe designer (Orlando Bloom) whose ardor cools when he experiences a colossal failure.