The role that broke her through was Cruel Intentions (1999), which she got after losing auditions for both Dawson's Creek and Buffy the Vampire Slayer. Those parts went to Katie Holmes and Sarah Michelle Gellar. When she landed Cecile Caldwell, the naive schoolgirl caught in everyone else's schemes, she turned it into the film's most-remembered moment. The kiss with Gellar's character won them both the MTV Movie Award for Best Kiss. After that: Legally Blonde, Hellboy, steady work in an industry where she never quite became the lead.
A 2018 Instagram post announcing her MS diagnosis reset her public identity entirely. 'I am disabled. I fall sometimes. I drop things.' Doctors had reportedly dismissed her symptoms for up to 25 years, blaming depression and anxiety. A stem cell transplant put her in remission. Her 2021 documentary Introducing, Selma Blair won at SXSW. In 2022 she showed up on Dancing with the Stars without her cane, scored a perfect 40 in her final performance, then withdrew when her MRI said stop. The illness defined the last seven years. Three new films say she's not done.
Optic neuritis at age 7 was her first MS symptom. Doctors missed it, then spent four decades cycling through depression, exhaustion, and anxiety as explanations. She has said she was 'happy' when the diagnosis finally came because it confirmed she wasn't making it up.