Gillian was born and raised in one of the nastiest slum areas of Milan. Her father was a decent man, but ineffectual; her mother was a very unpleasant alcoholic, treating both Gillian and her younger brother Firucchio very badly, which made them very close. They ran with various gangs while they grew up, and it was in an unpleasant fight, when Gillian was ambushed alone by another gang, that her teleportation powers came out. Eventually Gillian was able to leave the slums and go to art school due to her sheer brilliance, which allowed her to obtain a scholarship. She excelled, becoming quite famous while still at art school and in the process learning to when necessary hide her lower class accent and manners. Her brother also obtained a scholarship and became an accomplished physicist and engineer, specialising in sonics. While at art school Gillian also began a second career as the crime fighter Atalanta, doing her best to clear up the area she came from, then expanding her area of operations to much of southern Europe. She used money from her sculpting to finance her crime-fighting career and buy equipment. Only her brother knew of her powers and second career.
The superhuman known as Atalanta appeared for the first time in 1976, when she foiled a terrorist attack on an Italian military base near Naples which was led by the superhuman known as Bora. Her combination of teleportation with a powerful gun of unknown design proved very effective against the terrorists. After this incident she began to be seen fairly often fighting crime in various places around Europe. After several months she and the superhuman Legionne met, and shortly afterwards they began to work together with considerable effect.
Their partnership lasted for eight years until the fateful battle against Eurostar, in Venice in 1984 where Legionne was killed and she was seriously injured, and blinded. She only managed to escape by teleporting to one of her preset floating locations.
Gillian eventually recovered from her injuries, putting about a story that Gillian Umberto had been blinded in a car crash. Her brother helped her resume a crime-fighting career in the middle of 1987,using a sophisticated concealed sonar imaging headset of his own design. Although some doubted it could be the same person, she appeared to be fully recovered and continued her fight against crime in Europe. She had never really hated criminals before, treating them merely as opponents to be fought. However, since then she has harboured a deep hatred of criminals.
In 1993 Atalanta joined the European anti-terrorist task force, and assisted them in a number of successful operations. In late 1993 Eurostar destroyed Milan and the Essen-Duisberg conurbation. Gillian was first to volunteer to bring them down. Unfortunately, like the rest of the superhumans who went to take Eurostar in, she was caught in a massive anti matter detonation. Unlike them she did not die, but was somehow transformed into a creature of semi-substantial flickering energy and thrown into deep shock from which she took some months to recover.
Before the antimatter bomb blast, Atalanta was a fairly tall and athletic woman who appeared to be in her mid-30's, with short blonde hair (she wore a long blonde wig as Gillian Umberto). Her costume was all scarlet leather - knee high boots, skintight costume with gloves, belt, pouches, holster for her gun, and knife sheathes (as well as other knives in shoulder, back and boot sheathes). She wore a red leather jacket over the top and mirrored goggles which contained her sonar imaging headset.
After somehow surviving the anti-matter bomb blast, she became a semi-substantial being of flickering energy (looking something like a flickering, badly tuned TV picture) and all of her teleportation powers vastly expanded in capability.