Courtney is a boisterous 16-year-old girl, currently in High School. After her uncle - Ted Knight - dies, the funeral is held and Courtney is asked to go through her uncle's things when she finds a golden staff with an oversized hook on the end of it, she picks it up and it begins to glow a yellow hue. She was chosen. Knowledge is put into her mind on how to use the device and where it came from; the stars.

After discovering her uncle's true origins, she calls her mother and demands answers - she gets them, eventually. When she arrives home the following morning, she puts on some blue clothing and adds some details onto it with her sewing machine and becomes a secret hero known as Stargirl - in honor of her uncle who was Starman - taking down criminals in Portsmouth, Britain. After arriving home one day, she sees the news and discovers that America is being attacked by Darkseid, a tyrant who her uncle took down alongside fellow Justice Society of America members. She flies over to the U.S and helps the new Batman, Superman, Wonder Woman and Flash - as well as the original Green Lantern's twins: Jade and Obsidian.