A death omen is an apparition, of a deceased person or object. Usually, a death omen is an indicator that the person who is visited by it is going to die. The apparition can manifest in several places at once (bilocation), and to different people. Sometimes a death omen will try to communicate with the person they are appearing to, in order to warn them against impending danger.BoM
The ghost of Claire Becker is a death omen, Claire was killed by a crooked detective, Pete Sheridan. She appears to people he is about to murder. She tries to communicate and generates the letters DANASHULPS through printers, and computers. This is an anagram of Ashland Sup(plies), where she was killed.
When Diana Ballard kills Sheridan, Claire is put to rest.
The ghost ship Espírito Santo appears to people who have murdered a member of their family, before they are killed by the vengeful spirit of the Captain's brother. The ship also appears to Bela, who does not elaborate on the reason.
After the brothers summon the spirit of the Captain and the two spirits merge. The ship is not seen again.
In the 19th Century, Margaret Fox was a psychic who with her sister Kate Fox had a double act. Although Margaret had psychic talents, it was the charismatic Kate who got the attention. In the present day, angry that other, often fake, psychics are successful while he isn't, Jimmy Tomorrow binds the ghost of Margaret Fox to kill them. Her sister Kate tries to warn the victims of their impending death.