"Such a wonderful beast. As magnificent in intelligence as she is in scale. She is a work of art. Some of my finest work, in fact. I created her. I made her this way. They do not understand what she is, what she represents, the potential that she still has." Professor Keller
This giant aquatic monster is first heard in Episode 1 Thirty Years Of Mistakes. It is housed in a giant glass tank in the abandoned genome laboratory. The creature escapes after Blake and Jessie are attacked, and is on the loose in the Sub Levels of Tier City.
In Episode 4 In The Flesh, Rachel is trapped in an out-of-service lift where she listens to an Outbreak and Contagion Report. She hears Keller explain that there have been vast improvements since the viral boost and that the super-fast enzyme is optimising growth rate.
She then hears a report where Keller and her father, Max, are arguing. Keller is shouting that he is saving his life's work. Max shouts a warning before the audio cuts off.
In Episode 8 The North Hatch, Professor Keller explains that The Aqua, The Jurassic, Lithium are Rachel's home now.