Aria Campbell was split into twin beings when she was still in her mother's womb. This was done by her father, using the Gemini Matrix. The twins' birth threatened to kill both the children and the mother, until Francis Campbell made a deal with Darkseid to save them.

Years later, Aria and her twin brother Coda were turned over to be experimented on by Darkseid as per his deal with their father. But Francis Campbell feared the results of Darkseid's plans, so he helped Aria escape.

While Aria was on the run with her friend Lori, they were were rescued by Timber Wolf of the Legion of Super-Heroes. Unfortunately, Aria was later captured by Lobo and brought back to Darkseid. The Legion pursued Aria, and Brainiac 5 saved her during Darkseid's experiments. But Aria's brother Coda was dying and he sacrificed his life so that Aria would be a complete soul once again.

After merging with Coda, Aria became the being known as Gemini. Darkseid then goaded her into killing him, which was apparently his plan all along, to commit suicide by being destroyed by a being more powerful than himself. After destroying Darkseid, Aria seemed to have burned out her power, and returned to her father.

Months later, Aria returned to help a dying Timber Wolf, and her Gemini powers had returned. This time Aria used her powers to transport Timber Wolf through time and accidentally sent him all the way to the 20th Century.

In the 20th Century, Aria was kidnapped by the Dominators, who attempted to use her abilities to empower their own agents. Aria began to overpower their machines before being rescued by Timber Wolf, Thrust, and the government agency Point Force.

Aria disappeared during the events of Zero Hour, and it is theorized that she appeared in another universe where she adopted the new name Skylark.