Joanie Swift is a college student working as a secretary for the State University. One day, while typing equations for Professor Winklerod she read aloud the next one which was the formula Johnny Quick read to give him his powers (3X2(9YZ)4A. As she began typing she didn't realize that the typewriter began to melt. After she realized what she did her professor told her to take the papers to Dr. Halsey's office. As soon as she started walking she blew past her professor in a mere second. As she was moving fast she accidentally went past a room containing rare animals collected by Professor Gillquad. As she went by she blew open the cages and the animals were set free. She then went flying out the window. Johnny Quick saw what happened and went after her. Johnny saved her before she hurt herself, and she explained what happened. Johnny was shocked she read the formula, and she even began to think of teaming up with him. Johnny wasn't too thrilled so he tried to make her give up the idea by waring her out.
So he agreed and she went to make a costume. She then came back sporting an outfit similar to his. They then went to recapture the animals Joanie accidentally released. Each time Joanie found the animals before Johnny or helped him out of an pinch. They then went too the Professor to see what the last animal was. The doctor then show them a male mouse and saying its mate was missing. Joanie freaked out when she say the mouse that she jumped too the top of a bookshelf. She then found the mate and passed out. When she came too she no longer had her powers. She then asked Johnny to go and get the papers she read the formula on. As she read the equation nothing happened. It was revealed that Johnny changed the equation so that she would not obtain the powers again. Johnny felt horrible for changing the equation but it was for the best. She then said she will remember their time together, and hoped they could be good friends.
Joanie had the ability to run super fast and fly simply by saying the equation Johnny Quick used to obtain his powers. She only had her powers for half a day and never obtained them again due to Johnny retyping the equation. She was also skilled in running as she told Johnny that she was part of the track team once.