In 2000, Alexander won critical acclaim for her performance as Fran Boyd, a mother addicted to drugs in the Emmy Award-winning HBO miniseries The Corner. She later appeared in the films Emmett's Mark and Dark Blue, and starred opposite Rob Lowe in the Lifetime television movie Perfect Strangers. In 2002 through 2008, she portrayed the character of Alexx Woods, a medical examiner in the CBS police drama CSI: Miami. Alexander left CSI: Miami shortly before the end of the 2007-2008 season. Her final appearance aired on May 5, 2008. On February 2, 2009, she returned to the role of Alexx Woods for a guest appearance in the episode "Smoke Gets In Your CSI's". She returned again as Alexx Woods in guest appearances in the episodes "Out of Time" on September 21, 2009 and "Bad Seed" on October 19, 2009.