In the cargo bay, Zhaan and Rygel inspect the newly gotten supplies for infestation. D'Argo and Chiana are off-ship looking for a local cure for any parasites they might have. They return with a Vorc who is supposed to get rid of parasites. It runs off and is found only momentarily by various crew.

In the maintenance bay, Chiana and Rygel see a large creature they assume is the parasite. D'Argo is bitten by it and poisoned. The sensors pick up a creature.

Aeryn, John & Chiana trap it in a room. But all they find is the Vorc. When they ask him to show where the parasite is, a creature jumps out of him. They all believe the Vorc is the parasite, but no venom can be found in either the small Vorc or the large one. They decide to inject the Vorc with translator microbes to see if they can communicate. They are able to make some communication through Pilot. The Vorc clarifies it is not the parasite and will help find the real one.

It sniffs something and goes after it. It traps Rygel in the cargo bay. It goes after Rygel, so they shoot the Vorc. Rygel is also poisoned. They follow the Vorc into what they think is a trap and shoot it. After they incapacitate it, John notices a pod, which they'd been told was made by the parasite.

In the medical bay, Rygel begins streaming with spider-like insects, which fade back in. The Vorc opens the pod to reveal the real Rygel. Rygel explains how it reproduced him and made the pod to feed it's young with him. Aeryn and John race back and warn Zhaan on the way. The parasite-Rygel attacks Zhaan. John gets parasite-Rygel off and shoots it til it becomes all parasites. He then freezes them to death. They are able to cure D'Argo.