Mick St. John (Alex O'Loughlin) wears his coats with the collars flipped up, but in the poster artwork, his collar is flipped down. Alex O'Loughlin said in an interview that he didn't like that they changed the collar for the advertisements.
The main character, Mick St. John, was originally going to be called Mike Angel. The name was changed so as not to be confused with the Joss Whedon's vampire detective series Angel (1999). Similarly, the series title was originally going to be "Twilight", but the title was changed when Stephenie Meyer's book series "Twilight" became popular.
Sophia Myles (Beth) plays a woman who was saved and from her childhood watched over by never aging man she later showed interest in. In Doctor Who: The Girl in the Fireplace (2006) she plays a similar role, only the man is not vampire Mick St. John but the Timelord called the Doctor.
When the show went on hiatus during the writers' strike in early 2008, Sophia Myles (Beth Turner) cut her hair to her chin. When filming began again, she wore a wig beneath the bottom half of her hair to fit the character of Beth again.