She was the thirteenth person to join the Legion of Super-Heroes. She first appeared to try out for membership at the same time as Sun Boy and Bouncing Boy. At that same try-out, Supergirl and Brainiac 5 joined the Legion were admitted right away. eventually Shrinking Violet joined the Legion later, as did her fellow candidates Sun Boy and Bouncing Boy despite her shyness, Shrinking Violet is commonly known as Vi to her teammates, served as an exemplary Legionnaire. She later became romantically involved with Duplicate Boy of the Heroes of Lallor.

In current continuity, Shrinking Violet is also known as Atom Girl, a myth to all but the founding Legion members. She was considered a joke by the second wave of Legionnaires, until Brainiac 5 revealed her in the battle against Elysion of Terror Firma. She says she was exploring Brainiac 5's microverse and simply lost track of time. Invisible Kid used her name as a cover up to veil his tracks while spying on Brainiac 5. Subsequently, she assaulted Invisible Kid and after suspending him over the city, forgave him. She seems to quite like the image this gives her of being slightly crazy. She is fiercely loyal to Brainiac 5. Atom Girl overreacts to comments about her size and appears to feel hurt about appearing small in the eyes of the other Legionnaires.