Trivia: In the film poster, the "Not alone" on Halle Berry's forearm is written running from wrist to elbow. However, in the film, when she removes her bandages, it runs elbow to wrist.
Trivia: Halle Berry had a small problem while filming. In the middle of a take her wrist was fractured by Robert Downey Jr. He apparently grabbed her too hard.
Answer: The blood is not from Miranda; the drop of blood is a sign from the "dead girl" to tell Miranda that she should go to the place in the pic. Miranda goes the next day and that's how she finds her husband was a sadist.