Olivia Wilde played Remy “Thirteen” Hadley, an internal-medicine specialist and member of House’s later diagnostic teams.
Thirteen joins the team during the fourth-season doctor-selection storyline, when House evaluates a large group of applicants before choosing a smaller team. Her nickname comes from the numbered applicant identity used during that process. She is a skilled physician whose medical judgment is often shaped by the fact that she carries the Huntington’s disease gene.
The character’s name is Remy Hadley, while “Thirteen” is the nickname most commonly used by House and her colleagues. That distinction matters because the number is not her medical specialty or an official title.
Wilde’s role became one of the show’s most prominent later-cast performances. She also appeared in films including Tron: Legacy and later became known for directing Booksmart. In House M.D., Thirteen’s story combines diagnostic work with personal questions about inherited disease and uncertain prognosis.