NEW YORK — They play brother and sister on “Dexter.” Now in real life, Michael C. Hall and Jennifer Carpenter are husband and wife. Hall’s spokesman, Craig Bankey, announced that the couple eloped in California on New Year’s Eve.

Hall, 37, and Carpenter, 29, just finished the third season of “Dexter,” the Showtime series in which Hall plays the murderous title character. They’ve been quietly dating for about a year and a half. At their wedding, Carpenter’s grandfather’s wedding band was attached to her bouquet.

In other nuptial news, the Duchess is now a bride. Her manager says Fergie and Josh Duhamel have been married. Manager William Derella said by e-mail that the 33-year-old singer-actress, whose real name is Stacy Ferguson, and the 36-year-old “Transformers” actor were married Saturday at the Church Estates Vineyards in Malibu.