The first name of House M.D. character Dr. Thirteen is Remy, although the show most often calls her “Thirteen.”
Thirteen’s full name is Remy Hadley, and she is portrayed by Olivia Wilde. She joins House’s diagnostic team after the competitive hiring process that follows the departure of earlier fellows. Her nickname comes from the numbered applicant identity used during that selection storyline.
Thirteen is a physician with a private family history involving Huntington’s disease. Her possible genetic risk becomes an important part of her character arc, affecting her decisions, relationships, and views about uncertainty. The storyline also gives the series a way to explore genetic testing and personal choice.
“Thirteen” is therefore not her legal first name. It is a nickname that became her primary identifier within the hospital and among viewers. The character’s full name is stated in the series and documented in reference sources.