Kayla's life was changed forever the day she had an interview at Four Freedoms Plaza. She had attempted to get a Secretarial position, but was certain she hadn't gained the job as the hiring manager didn't like the way she dressed.
As she rode the elevator back to the lobby, Wendell Vaughn noticed her crying. He stopped her to ask if she was okay, and she explained everything about how she didn't get a job just because of how she dressed, he offered her a job with Vaughn Securities on the spot.
Wendell left her abruptly giving some vague excuse but forgot his office lease he had just gotten for his business.
She went to return it to him but couldn't find him, she accidentally wandered onto the Fantastic Four's penthouse where she was taken hostage by the Angler doing battle with the Human Torch and Quasar. In the end she was saved and the Angler was imprisoned.
She was rather open about her attraction to Wendell and eventually they began to date, when she opened up to Wendell about her feelings, he responded that he felt the same way and revealed his secret identity to her. A jealous Moondragon attempted to force her into the arms of Quasar's friend, Makkari with mental control.
Shortly thereafter, she was held hostage by Maelstrom for a time, but was freed by Ghost Rider.
Later, when Quasar returned from another dimension with a previously unknown power-source called the Star Brand, he accidentally passed it on to her without either of them knowing, he simply thought it had burnt out getting him back to his own universe.
Soon, she found herself embroiled in her own adventures, being kidnapped by aliens, flying on her own, demonstrating great physical strength and fortitude, and even resurrecting herself. All the while her "friend" H.D. Steckly waited for her to tire of the stresses placed upon her. Meanwhile, Quasar returned on Earth started to look for her girlfriend, asking to common friends, and finally talking to her brother Devon, who was living in Long Island with their father.
Finally, as Kayla was ready to give up the power, H.D. offered to take the Star Brand, and Kayla trusting her agreed, it was then H.D. revealed herself to be Erishkigal, a deviant bent on universal domination.
Quasar with the help of the Silver Surfer was able to defeat Erishkigal, but at the cost of his own pride. The great powers of the universe not knowing where else to put the brand now that it was in our universe gave it back to Kayla, feeling it was as safe there as anywhere.
After suffering a catastrophic defeat at her hands, the Black Fleet's last ship came to Earth. Led by Skeletron, they kidnapped Kayla as Quasar defended Earth from a feint they had made to knock Earth out of it's orbit.
They took her to the Stranger who managed to manipulated her into giving it up. This caused a White Event over the Stranger's Lab World and brought the Earth from the same universe that the Star Brand was from into the Marvel Universe.
The powers of the universe quarantined the new Earth and transported Kayla to the planet where the Star Brand belonged forever separating her from Wendell. As compromise, the Living Tribunal offered Quasar the chance to give up his responsibilities and stay with her on the planet, Quasar while very tempted, he felt his work wasn't done and refused.
Kayla continued on and began a new life on the new Earth.
Powers imparted by the Star Brand
• Destructive blasts, up to the equivalent of nuclear explosion in force (this last power is problematic, as the blast manifests as a sphere centered on the wielder indiscriminately destroying everything in his vicinity).
The brand itself is roughly the size of the palm of the hand and as far as has been shown is immaterial and effectively only two-dimensional. The Brand is utterly black in color and is smooth and warm to the touch. As long as it is somewhere on their skin the bearer may wield its powers. The brand can be transferred to another part of the body if the bearer wills it by skin-to-skin contact, thus the bearer can choose to place the Star Brand anywhere on his person, willing it into his hand then placing it anywhere on their body. However, this transfer involves some energy discharge, and the brand will burn off any hair it is placed over. The Star Brand and its power can be transferred to another person, but former owners are always left with a remaining residue of about 10% of its power, a residue which regenerates and in time will grow to equal that of the original. In the series it was stated that the power of the brand is infinite. So 10% of infinite power is still infinite power.