Born Lois Brown, Lois London is the younger half-sister of the mutant recording artist, Dazzler. She was born to Alison's mother, Katherine Blaire, and her lover, Nicholas Brown. At a young age Lois watched her father beat her mother, who spiraled into drug addiction. Eventually, Katherine sobered up and took Lois with her as she fled her abusive lover. Katherine took on a new identity, Barbara London, and changed Lois' surname as well. Lois grew up as a normal teenager and attended State University. Despite being a big Dazzler fan, Lois never knew Alison Blaire was her own half-sister, since Barbara was too ashamed to discuss her sordid past.
Meeting Dazzler
After Dazzler reunited with Barbara London, Lois introduced herself. Lois, however, was unaware of Dazzler's mutant powers until Alison used them to help the pair escape a building fire. Lois kept Alison's mutant powers a secret. Lois soon became a target for trouble as Dazzler's then-enemy, Rogue, attacked Lois in her dorm room. Dazzler, with the help of Luke Cage and Iron Fist, was able to evade Rogue and draw her focus from Lois, as Lois watched helplessly.
Powers emerge
Lois soon became plagued by headaches and migraines, which she was hoping was a simple case of mononucleosis. After leaving a Dazzler concert and walking the streets alone, Lois was approached by a hobo. When she attempted to get away, Lois's hand crackled with a mysterious energy. She accidentally touched the hobo with her crackling hand and he suddenly dropped dead. Lois fled to Alison's apartment for safety, confused and panicked over what had occurred. Dazzler decided to take her younger sister and flee New York. While stopped at a motel, Lois attacked and killed the motel manager's cat after it scratched her. When her sister found out, she took Lois and fled again. Later, mysterious photos emerged of Lois killing the hobo in New York along with a blackmail message. The blackmailer demanded that the two sisters assassinate a man in California, or else the photos would be given to the police and Lois would be arrested. Fearing what the judicial system would do to a mutant, Alison convinced Lois to go along with the plan. Lois's world turned upside down when she discovered the target was her own father, Nicholas Brown. Brown had sent an assistant to search for Lois, but the assistant went rogue and attempted to gain money in blackmailing Lois into killing her own father, his boss. The plan failed, and Brown and Lois were reunited with Dazzler in the middle. Although she had been protected by her half-sister and just reunited with an abusive father she barely knew, Lois decided to stay with Brown. Brown, now very wealthy and well-connected in California, offered Lois a sense of security she needed. Lois and Alison parted ways, with Alison angry and hurt.
Necrosha
Prior to the events of Necrosha, Lois was still living with her father and the guilt that she killed a man a few years ago. One evening at dinner with her father, he does everything he can to make her feel better, so she pretends everything is fine. While watching the news she sees a report on the X-Men moving to San Francisco and sees her sister Dazzler with the other X-Men. It is revealed that Lois's feelings toward her sister have soured and that she now hates her. One night Lois receives a call from her father's secretary claiming her father is drunk. Lois goes to his office where he calls her a monster and asks for Allison. He blames her for the destruction of their family and slaps her. She turns around and tells him he was the one who destroyed their family, not her, and in a fit of rage kills him. Afraid of what she has done, she tries to kill herself with her powers. Her father's secretary then enters and reveals everything will be fine while trying to calm her down. Eventually it is revealed that Selene has been pretending to be her father's secretary in order to sway Lois to embrace her powers, give in to the pleasure it gives her to kill and turn her back on humanity and any attachments to them. Selene then recruits her to her cause and gives her the name Mortis. As a part of Selene's new Inner Circle, Mortis travels to Selene's birthplace, Rome, and then New York. There, they slaughter the New York branch of the Hellfire Club before going to the ruins of Genosha. When the Inner Circle are dispatched to retrieve the mystical knife necessary for Selene's ritual, Mortis draws first blood when she casually kills Diamond Lil. She then uses her powers against Wolverine, but his healing factor allows him to survive the usually fatal effects. She then confronts her sister, claiming that she hates her. Wolfsbane battles Mortis during the final fight, commenting how Lois smells like Alison. Furious, Lois declares she is nothing like her sister. Wolfsbane agrees, saying Alison is a good person who would have helped Lois. She then slices Mortis' throat, ending her threat. Blink, injured herself, later flees Necrosha with the wounded Lois.
After Necrosha
Lois confronts her sister Alison once more, enlisting the help of Arcade in an attempt to kill her. The battle ends with Lois being defeated. Alison brings her to Utopia, causing conflict with Cyclops, as the murder of Diamond Lil is not easily forgotten by him or the other residents of Utopia. Alison defends her decision, pointing out that others living on the island have killed before, and that Cyclops himself also has a murderous sibling. She seeks the help of Psylocke, who places Lois in a telepathically-induced coma. She senses that Lois has suffered a great trauma, and that her psyche has shattered. Psylocke agrees to work with Lois on the astral plane, repairing the psychological damage done by Selene and her parents, but warns that it could take years to rehabilitate her.
Powers and abilities
Lois London generates a disruptive field of unknown energy that affects the molecular properties of any matter she comes in physical contact with. At first, her power manifested in times of extreme stress. In later appearances she demonstrated greater control. Her touch can kill a living being instantly, causing a disruptive surge that mimics the effect of a fatal heart attack. Used on inorganic matter, her power destroys the molecular bonds holding the matter together, causing the object to liquefy or disintegrate. Her powers have been shown to be ineffective against her half-sister Dazzler.
