She had plans to study either psychology, environmental science, or forensic science at Simon Fraser University when a casting director for the CBC TV series Edgemont contacted Eric Hamber Secondary School, looking for an exotic-looking girl to play the part of a Chinese Canadian, Laurel Yeung on the Vancouver-shot show. Kreuk's drama teacher convinced Kreuk, who had no previous acting experience other than in musicals at her high school, to audition for the role. To her surprise, she won the part.
In the summer of 2004, Kreuk joined the cast of the Sci Fi Channel miniseries Legend of Earthsea, starring Shawn Ashmore and Danny Glover and based on the novels by Ursula K. Le Guin. Her character, Tenar, is the pupil of High Priestess Thar of the Tombs of Atuan (played by Isabella Rossellini) and also the love interest of Ashmore's character. The two-part miniseries, filmed in Vancouver, was directed by Rob Lieberman and co-produced by Lawrence Bender of Pulp Fiction fame. It was broadcast on December 13, 2004.