Ben, Gwen, and Kevin go camping in the wilderness (as Gwen believes that this is the only place where Ben can go that his fame will not catch up to him and ruin his chance of fun). Kevin and Ben car race to determine who has to cook and, while they are doing so, what Kevin believes to be an escape pod falls from space. While trying to open the pod, Gwen mildly electrocutes herself. The pod opens, revealing a nude blonde girl. Gwen gives the girl some of her spare clothes and the girl tells Gwen and the rest of the group that her name is Eunice, though she doesn't remember anything else about herself and seems to have almost complete memory loss. As the camping trip continues Eunice is revealed to have a strange connection to nature (being able to seemingly attract wild animals, tame them, and absorb their innate abilities). Ben begins to develop a crush on Eunice against the disapproval of Gwen (who believes that Ben is not officially broken up with Julie). Sunder comes to Earth on a mission to find Eunice. While Ben is on an unofficial date with Eunice (visiting a ravine), sunder attacks the pair and they are separated when Eunice absorbs the power of a bunny and hops away. Ben, Gwen, and Kevin find Eunice at the top of a mountain and demand that she tell them why Sunder is after her. Sunder soon arrives, tricks Eunice by saying that he can tell her where she came from, and activates a button on her neck, which transforms her into a cylindrical device. Ben stops Sunder from escaping with Eunice by transforming into Ultimate Cannonbolt and subduing the bounty hunter and Kevin returns Eunice back to her human form by operating the cylinder like an Omnitrix (a similarity which Ben had explained earlier). As Eunice interrogates Sunder about her past, Azmuth appears and tells Eunice that she is no more than a prototype for the Omnitrix, once known as the Unitrix, and that he freed Sunder from the Null Void to retrieve the Unitrix for him when it was accidentally lost. Ben convinces Azmuth to not put Eunice into storage (believing that she has developed a human conscience and should thus be treated as a human being) but to instead leave her in activation on Primus as one of his aides. Before she leaves for Primus, Eunice gives Ben a blue flower that she had found earlier as thanks for helping her.