Penelope the garden spider lives in Julia's backyard. A mosquito lands in Penelope's web and she eats it. It gives her gas. When Julia is bitten by a mosquito, she gets sick. The doctor finds that she has the Zika virus and notifies the Health Department. Traps are set up to catch mosquitoes. If Zika is present, the backyard will be sprayed to kill the mosquitos. Penelope realizes that she and all the other creatures in the backyard will be killed if this happens, so she begins a program to keep the mosquitoes out of the traps. When no Zika mosquitoes are found, she and her other backyard allies realize they are saved.