Kim and Ron are asked to guard Ray-X, a top-secret ray device. But just before going to the lab, Kim catches a cold from her two little brothers. While Kim is guarding Ray-X, Drakken and Shego attempt - and succeed - to steal Ray-X, but not before Shego catches the cold from Kim. Drakken needs help with Shego sick, so he contracts with Duff Killigan to help him exploit Ray-X. Meanwhile, Ron heads to Drakken's lair and retrieves Ray-X, but catches Shego's cold. Drakken comes down with the cold, and Killigan then hires a temp to take his place. They then re-steal Ray-X back from Ron. Back at the lair, Killigan is now sick, just leaving the temp, who is relishing his new career. With everyone else sick, Jim and Tim, now well, go back to get the Ray-X. The temp catches the tweebs, but Kim and Ron free them. They all catch the temp as he tries to "quit", but the Ray-X machine is damaged. Kim and Ron return the Ray-X to the scientists, apologizing for letting it get damages. Out of curiosity, they ask what Ray-X was supposed to do. "Cure the common cold," they reply.
—Tony B-4