"I'm not in the business... I am the business."[src]
Being the founder of the Tyrell Corporation, Eldon Tyrell had access to unfathomable wealth, power, and technology. In order to colonize and explore habitable areas for Off-world Colonies, the Tyrell Corporation manufactured Replicants. These replicants were just like humans, although often possessing superior strength and greater or equal intellect in comparison to their genetic designers. The Nexus-6 variety of Replicants up to 2019 possessed strength and intellect, but were not equipped to live longer than 4 years in an effort to curb rebellions and limit their danger (despite their effectiveness in colonization and hazardous labor).
Because of his status in society, Tyrell developed Rachael alongside these Nexus-6 models, although including significant differences. She was implanted with memories given by Tyrell's niece to better control her. Falling back on memories gave Rachael a sense of reality and purpose, evening out her emotions and testing to see the effectiveness of such an experiment for future Nexus models. Tyrell also gave her more than four years of life; the exact amount remaining unknown.
Given that Rachael had implanted memories and was not told she was a replicant, she believed she was human.
Voight-Kampff testing and meeting DeckardEdit
Deckard was sent to the Tyrell Corporation by Harry Bryant to use the Voigt-Kampff machine and test a Nexus-6 to better understand what he would be up against. Being aware that a Blade Runner was visiting the complex, Rachael entered the meeting room of the Tyrell Corporation building and greeted Deckard after commenting on how the corporation's owl was artificial, as were most animals on Earth in 2019.
Rachael asked Deckard if he had ever retired a human by mistake. Deckard simply stated that he had not, which resulted in Rachael questioning if it was always a risk that he would kill a human. However, the conversation was cut short when Tyrell entered the room and requested to see the Voight-Kampff Test on a human subject. Trying to convince Deckard that Rachael was human, Tyrell insisted that she be used as the test.
After over 100 questions, Tyrell asked Rachael to leave him alone with Deckard. Deckard determined that Rachael is a replicant, to which Tyrell revealed that Rachael was implanted with memories to provide a cushion for her emotions. Tyrell also informed Deckard that Rachael is unaware of what she is.
Reconciling with DeckardEdit
The next evening, Rachael left the corporation and went to Deckard's apartment. Rachael entered the apartment elevator and sat hidden in the corner of the elevator and waited for Deckard to return. As Deckard entered the elevator and the elevator stopped at the appropriate floor, Rachael revealed herself to Deckard.
Rachael walked with Deckard to his door while explaining how Tyrell would neither speak to her nor see her concerning her test. Deckard attempted to send Rachael away. However, after entering his apartment room, he allowed her to enter.
Rachael entered and showed a picture of what she believed to be her mother and explained that she had memories of her childhood with her mother. Rachael wanted to further explain, but Deckard cut her off to recall to her the memories of her childhood; informing her that he was only aware of her memories because they were imprinted.
Deckard explained to her that her memories were false due to their connections with Tyrell's niece. Shocked by the evidence found, Rachael began to cry in silence. Deckard then told her it was a "bad joke," and apologized, but the damage was done. He offered her a drink, but as Deckard went to get a glass, Rachael dropped her photo and walked out of the apartment.
While Deckard investigated Zhora at Taffey Lewis' bar, he called Rachael by Vid Phone. Deckard asked for her to come to the bar to relax and spend time with him, but Rachael declined, saying that "wasn't her type of place," and hung up on him.
Later that evening, Rachael was out in the city when she came across Deckard being beaten savagely by Leon. Rachael picked up Deckard's abandoned gun and shot Leon in the head, killing him just moments before he could eliminate Deckard.
After saving Deckard's life, a very rattled Rachael went back to his apartment to hide out. Rachael asked Deckard if he would still retire her if she was to leave Los Angeles, to which Deckard replied that he would not, but another Blade Runner probably would.
Drunk and exhausted from the night, Deckard laid down on his couch and fell asleep. Rachael sat down at his piano and let down her hair as she began to play a melody. The music woke Deckard, who joined her at the piano. Rachael explained that she remembered taking piano lessons, but she was now unsure if the memories were hers, or implants from Tyrell's niece.
Deckard compliments her playing, then leaned in to kiss her. Uncomfortable with the gesture, Rachael withdrew, and tried to leave the apartment. Deckard became angry and violent, slamming the door shut so she could not leave and pushing her against the wall. As she cried, he ordered her to tell him to kiss her. She did and he kissed her forcefully. Despite her emotional distress, she soon consented to his advances.
Leaving the life behindEdit
As they left, Deckard came across an origami figure of a unicorn left by Gaff to show that he had been at the apartment while Rachael was asleep. As Deckard examined the figure and turned towards Rachael, and they both departed toward an uncertain future together.
Months after leaving the city, Rachael and Deckard lived together in a cabin in Oregon. Rachael was kept within a Tyrell transport sleep module that slowed down her aging process. Later, Sarah Tyrell – Eldon's niece and Rachael's templant – ordered Tyrell agents to remove the sleep module from the cabin, which was promptly set on fire. Afterwards, the sleep module was returned and turned off. Sometime later, Dave Holden investigated the cabin, finding Rachael dead inside the sleep module.