Little is known of the childhood of Suzy Sherman apart from that she was raised in California but her father Toby Sherman, and her mother.
In her teen years, Suzy was struggling model in Southern California. Since she was rapidly developing muscles and the agencies thought she was too "buff" to be a model. On an audition, Suzy was suddenly attacked by a Sentinel, a left-over minion from Onslaught.
The Sentinel implied that she was actually a mutant Kree-Warrior, though her exact origins are still unclear today. Reporters who saw the fight between Suzy and the Sentinel ran to interview her. During the interview she kept using the term "Ultra", which led to the press dubbing her "Ultra Girl". Suzy began to receive endorsements, and thought that being Ultra Girl was her ticket to stardom, so she and her friends designed a costume from sports apparel she had received from past modeling jobs.One of Suzy's friends, Amber, tried to convince her to abandon the superhero idea, but Ultra Girl was set on it, even fighting against the villain, Effex, alongside the New Warriors. Together the Warriors and Ultra Girl defeated Effex.
After a mission with the Warriors, Ultra Girl learned that Amber was in fact "Ambra", a Kree agent sent to Earth to watch Suzy, whose real name was Tsu-Zana, discovered her friend Amber & other locals were secretly Kree and that they expected her to serve as Kree messiah. Ambra also informed Suzy that many of her friends (even her childhood doctor) were Kree. It was said in the Kree writings that Tsu-Zana was to be the Ultimate Unifier, so she could eventually restore glory to the Kree Empire. They asked her to abandon her superhero career, as to not draw attention to the Kree.
Civil WarThe honor of working with the New Warriors is now haunting her, as the Warriors are blamed for an explosion in Stamford which caused the death of hundreds of people, including children. Ultra Girl is one of the New Warriors whose civilian identities were publicly outed on an Anti-New Warriors website. Teaming with the remaining Warriors and She-Hulk, they shut down the website and discovered it was in fact run by former Warrior, Hindsight.
Ultra-Girl was a member of Captain America's Secret Avengers. She was seen among the super-heroes rescuing Captain America during Tony Stark and Steve Roger's private meeting to make one more attempt at settling their differences. After the end of the war, she decided to comply with the Superhuman Registration Act.
Post Civil WarUltra Girl is now part of the Initiative. Sherman is seen on the bus of registered trainees headed for Stamford. Ultra Girl is injured while fighting the forces of HYDRA. She later accompanies Rage, Hardball, Cloud 9, Komodo, Triathlon, Thor Girl, and Slapstick to fight the Hulk. It has also been revealed that she and Justice have started a relationship.