Life in Paragon (Tanker): Rachael lived a rather quiet and sheltered life eventually obtaining a scholarship to study Library Science at Oxford. While there, she roomed with a student studying 'science'. However, her roommate was being observed by Crey for recruitment. The agents of Crey decided to "threaten" Rachael's roommate by exposing Rachael to a near lethal dose of atmospherium. However, the radiation interacted with Rachael's DNA causing her to increase in density. This provided her with super strength and extreme resistance to physical damage. She rescued her friend and fled to Paragon City. As a side effect of the mutation, she grew several inches taller.
Life in the Rogue Isles (Brute): After accidentally tearing a tag off of a piece of furniture, Superhero Rachael Storm was arrested and thrown into the Zig. Realizing that she could be valuable, Lord Recluse sent agents to break her how. She doesn't willingly serve Arachnos, she is merely trying to prove her innocence and return to her beloved Paragon City from which she was exiled!