They are the cast of the show(Dexter)

Plot of the show

Spoiler Warning:Plot and/or ending details follow.

Orphaned at the age of three and harboring a traumatic secret, Dexter (Michael C. Hall) was adopted by a Miami police officer who recognized his homicidal tendencies and taught him to channel his gruesome passion for human vivisection in a "constructive" way—by killing only heinous criminals (such as child molesters, mob assassins, and serial killers of the innocent) who have slipped through the justice system. To satisfy his interest in blood and to facilitate his own crimes, Dexter works as a blood spatter analyst for the Miami police. Although his drive to kill is unflinching, he is easily able to emulate normal emotions and keep up his appearance as a socially-responsible human being. He is well-liked by most of his colleagues, his girlfriend, and her children.