As in the episode 'Ice', Mulder and Scully take another field trip with deadly consequences.

At the start, we see a group of loggers quickly rushing from something that we don't know but they obviously do. But when two of them fall over and suddenly millions of green flys descend on them we get a glimpse of the terror they were running from.

Mulder is interested when he has heard that all 30 loggers had disappeared from the site so he takes Scully along with him for a nice trip to the forest! They meet up straight away with the security chief, Steve Humphreys who believes that it is a simple case of angry Eco-terrorists but Mulder wants to find what really happened out there. On the way to their camp, their tyres are flattened by road spikes so they have to hike up there. The two agents want to investigate straight away and while searching the forest woods they find a mysterious cocoon which contains a human body drained of all it's fluids. Scully tells Mulder that only an insect could have done this and he replies with the subtle remark "Incy, wincy spider".

Going back to the camp they meet up with an eco-terrorist called Doug Spinney who seems to know what's behind the killings. Telling Mulder that the insects only come out at night he says "Darkness is our enemy". Mulder concludes that while the loggers were cutting down the trees they must have released some ancient exotic insect after analysing a tree stump. Spinney observes that they "must have woke up hungry".

Steve Humphreys leaves the camp only to be devoured by the insects in his car and trapped in another cocoon. Meanwhile, Mulder lets Spinney go across to the other side of camp for a jeep because all cars are dead at the camp and they are trapped. As Spinney took the last of the gas, the agents aren't sure whether they have enough to keep the generator running to power the lights which will keep the bugs away. Just as the generator stops, the sun comes up. Determined not to waste any time, Mulder and Scully and the ranger decide to go down to Humphreys car where they find him in the cocoon. Here they also meet up with Spinney who gives them a lift in the jeep but it is stopped again by Spinney's road spikes!

Spinney gets out of the jeep to take a look but is chased by the bugs into the night. The deadly insects then start swarming through the vents of the jeep and the agents are cocooned. They are found in the morning by a quarantine squad where they are saved and contained in a high security building. When Mulder wakes up he asks what the government will do if the bugs start taking over major cities. One of the officials replies that they will be using pesticides to kill them off. Mulder asks "What if that doesn't work" and the man replies "That is not a option Mr.Mulder". Watch your backs!