Members of Mercury's family. They are accomplished superheroes and speedsters.
Grandma Swift a.k.a Silverbolt. One of the early golden age speedsters. Eventually retired and settled down with a man to have a family.
Uncle Chase a.k.a Comet. As a young scientist, Matt Chase was experimenting one night with a formula that his friend, James Swift, found in his attic. The two young men were finishing the solution when an explosion happened, forcing the solution into their muscles. When the friends woke up, they discovered that they had super speed. Eventually the two went their separate ways, James joining the World Alliance while Matt decided that he was best suited for teaching the next generation of superheroes. He is currently mentoring The Irregulators.
James Swift a.k.a Silver Streak. After a freak accident that left him with super speed, James decided to help people with his new powers. After working a while he joined the World Alliance - a group of over a hundred superheroes scattered around the world, using their powers to protect the normal people living their lives. It was there that he met the love of his life and follow speedster, Helen Quick.
Helen Gale a.k.a Tempest. Born with powers that developed later in her life, Helen decided early on that she wanted to work for equality for everyone around the globe. With that in mind she joined the World Alliance, where she met her eventual husband, James Swift.