His wife having kicked him out Roger asks to stay with Lisa and Heather, who doesn't take long to get fed up with him living with them. She is going on a school trip to the museum, full of other old things, which does nothing to cheer her up. There she meets Dr. Bing, who looks after the insect section of the museum. Meanwhile Dr. Morris is trying to find out why virus carrying Mosquito's are appearing, before they should be out of hibernation, and are biting rich, prosperous businessman.

With more and more people being bitten by insects carrying a killer virus it seems as if there is some sort of human control over these concerted attacks. Can Theo and Michael find out if this is the case and , if so, find the person controlling them before it is too late?