Gem Antonelli, a native of Los Angeles, was part of a series of experiments carried out by the group called INTERNATIONAL OPERATIONS under the control of the director of the Department of Science and Technology--Ivana Baiul. As Lynch broke into I.O. security to rescue a group of youngsters from her experiments, Ivana was forced to escape and moved her base to Isla Caballito to continue with her experiments on the frozen specimens she managed to carry with her. One of those GEN-ACTIVE kids frozen in liquid nitrogen, was Gem herself.
Gem is a neuro-dominator, able to temporarily control the bodies of others. After passing hard training she earned a place in DV8, Ivana's group of super-powered operatives. However, due to her weak stomach, she almost got eliminated (literally), but somehow got chosen by Threshold, Ivana's right hand, to be part of his team. Unlike her DV8 partners, Gem didn't take her activities so seriously and constantly fooled around.
Due to an incident involving Bliss , she had four split personalities in addition to her normal persona. This made her teammates very uneasy around her and lead them to believe she was quite insane and unstable. Her four extra personalities were:
Copycat has multiple personality disorder. Besides her main personality, she has four others.
Soldier: This personality is rough and tough. Does whatever it takes to get what she wants.
Nihilist: Completely paranoid and hates everything, including her own life.
Gemma: A five-year old kid prone to fits and lots of whining.
Spy: Personality that analyzes every situation. Cold and calculating.
The three personalities are protective of Little Gemma. Ivana and her teammates believed the personalities were a reaction to the booster drugs all DV8-members received to increase their powers.
Gemma's already unstable mental state would receive a further blow when she was temporarily captured in an attack on a foreign scientific facility. She was forcibly made to experience a white room with no reachable ceiling or walls.
When Threshold turned against DV8, he mentally attacked Copycat, putting her in a coma. Gemma stayed in the coma for a long time, and when she woke up, something had changed: The link between Bliss and herself had been broken and her real mind slowly started to heal.
The final trigger happened when she tried to possess her teammate Freestyle. Her mind was restored and her alternate personalities disappeared.
Shortly afterwards DV8 was disbanded and Copycat left with her teammates Sublime and Frostbite to try to live a normal life. They later joined up with Genevieve Cray, a female clone of Michael Cray Sublime's father.
Copycat can mentally possess another person. While possessed, they physically copy every action she takes. Normally, she can only posses one person at a time. However, with concentration, each personality can control someone.