Doctor Cooper was one of three Humans that Keenan Lane (or really, Nach'lih kallah-vahh) had tucked away in storage in his Vortal realms. The first being Rhea Mercer from Rapture, and the other a young man [undecided name/details]. Rachel had been on Lane's 'list' for a good number of reasons, and it was because of his implanted suggestions that she became a scientist - and not, as she often claimed, because she was chasing Winslow Freeman's affections and he was in the science club in school. Yes, that Winslow Freeman - Gordon's father. Oddly enough, Rachel was put in stasis at approximately the same age as Gordon Freeman - in the same year he was born.

Though she was born in the southern portion of Colorado in a very small agricultural outpost community, her parents soon moved to Seattle where Armacham Technologies were setting up shop. Her family and the Freemans were reasonably close, though in the era she was only expected to go 'so far' before 'getting back to the kitchen'. Rachel proved her classmates were idiots, garnering her a scholarship into a local technical school, and then into MIT. In the emerging fields of computer engineering, programming and electronics, Rachel became Doctor Cooper within five years of graduating high school.

Aperture Science used to have a facility in Cleveland Ohio. With a number of other locations in that area - some deeply within salt mines and very rarely in populated towns - the nondescript building didn't seem like it was 'all that interesting' when she first saw it. However, the massive facility reached five stories below ground, and it was there that Rachel cut her teeth in the industry. The Borealis Alternative Temporal Shunting Harmonics Investigatory Think Tank was, in short, exactly as its acronym implied: Batshitt. It was a time travel research facility.

Rachel's job assisting the 'old men' in the facility (they weren't old, merely 'of the generation that believed women were secretaries and not scientists') was frustrating for a time. But in 1976 when Cave Johnson 'died' (cloned, put into a new Icarus-supplied body, and subsequently put into stasis at Armacham's Enrichment Centere) she was approached by a tall man in a blue suit and given an offer. In exchange for some undisclosed 'deal' later on, Rachel was placed in the Prototype Hardware department and let loose. Because of her work, the Borealis was on schedule to be tested out within three years. Before that three years was up, however, Rachel had earned herself a good chunk of vacation time.

Treating herself to a trip to Jamaica, Rachel had no idea that the Borealis was going to be turned on in her absence. And it's a good thing she was absent. The facility vanished whole, top to deepest basement, and was essentially never there to begin with according to any research done later. While it's clear that something happened, something worked, Rachel wasn't on hand to view it. When it returned (and where) triggered the Resonance Cascade and Synchronicity Events - but she was still slumbering in Lane's Vortal stasis tube. Plucked from her hotel room, her 3 week vacation turned into a 50 year long rest.

Because he felt afraid that his Vortal constructs would not continue without his energy to supply them, Lane released his trio of 'kept' individuals. Rhea did not adjust well, Raven's story bears that out. However, Rachel was positively thrilled to be in this new - albeit destroyed - world.

Learning of all the technology at their disposal, Rachel soaked up the theory, design and implementation of a number of Ulathoi devices. One of them, similar to Aperture's hand-held portal device, but closer to the 'zero point energy field manipulator', the gravity gun, she repurposed into a stunningly handy 'gun'. It has a number of different triggers, modifications to its output, and can be tweaked on the fly to allow for a variety of different results. Mostly, hitting things in a wider or narrower cone of impact...

Because she was 'on hold' as long as she was, Rachel knew there would be a lot of changes to the people that she had known, and those who she'd be working with currently. It was a bittersweet reunion when she met Gordon Freeman for the first time - he looks stunningly like his father, according to her. That, and realizing that she was only two years younger than Eli Vance... who would die of old age within a dozen years. Rachel decided to put those old Armacham stasis units to good use, they were scattered around in almost every City that still existed after all. So rather than tucking into bed to sleep every night... Rachel wears herself out for a couple days, and then crashes into a stasis unit. Healing injuries overnight, and occasionally selecting skill downloads to be implanted while she's resting, Rachel has forwarded herself into the future indefinitely.

She was one of the few people that Lane outright trusted - oddly common to strong willed and rather blunt women - and was also, apparently, the only one who knew of his affair with Cave Johnson's wife Caroline. She originally thought (and told him so) that that was why he'd singled her out. It was actually news to him that she knew, so... no. That wasn't it. However, he would claim laughing at the idea, he did put her there because she was really smart.

Even though her own world is in ruins, and Rachel has participated to a large degree in getting the remaining civilization into a good comfortable state, she is still eager to see what else is out there. After all, she worked on a time travel device. The fact that she is now able to move between universes is something she will lapse into giggling about. She's enjoying herself in Paragon City, and though she knows it's 'wrong' to ally herself with certain groups, there's a particular allure to some technologies there that she might not be able to resist. She's taken her "pewpew" gun on the road, as it were, and she's not afraid to use it.