Larisa Romanovna Oleynik is an American actress. Oleynik began her career as a child actor, first appearing onstage as young Cosette in a national touring production of Les Misérables (1989–1991).
She was subsequently cast in the title role on the Nickelodeon sci-fi series The Secret World of Alex Mack from 1994 to 1998. She also began a film career, starring in an ensemble cast as Dawn Schafer in the film adaptation The Baby-Sitters Club (1995), and in a lead role in the teen comedy 10 Things I Hate About You (1999).
Oleynik subsequently had a supporting role in the comedy 100 Girls (2000), after which she starred opposite Nastassja Kinski and Scarlett Johansson in the period film An American Rhapsody (2001), and the independent drama Bringing Rain (2003). She later had supporting roles in Atlas Shrugged: Part II (2011) and the horror film Jessabelle (2014). From 2010 to 2015, she had a recurring role as Cynthia Cosgrove on the AMC series Mad Men, and a voice role as Icy on the Nickelodeon revival of Winx Club (2011–2014).
