Darien encounters a bizarrely-aged woman and soon becomes infected with the same disease, causing him to rapidly age.

Hobbes starts trailing his ex-wife, and gets arrested as a stalker. Hobbes believes his ex-wife Vivian's new fiance is a crook. Darien thinks he's jealous, but it turns out Hobbes is right, and they're assigned to the case. It turns out that the fiance is an undercover agent for Naval Investigations. They all team up to find the culprit in an illegal arms sale. They get captured but Darien manages to escape with his invisibility, and capture the bad guys. Hobbes is impressed with the fiance, Brock, and reconciles with Vivian.

The Official is assault by an invisible man and Fawkes is suspected - Darien and Hobbes work to clear Darin and find the true assailant.

Unable to craft their own invisiblity gland, the Chinese government sets out to steal the American one. Unfortunately, they have the idea that Bobby Hobbes is the invisible member of the team. Fawkes and Hobbes go into hiding, but Bobby gets nervous. After several chases, Hobbes apparently dies in a car crash. It's a set-up, but he turns up at his own funeral to look on from a distance, and is captured there by the Chinese. The Agency tracks him to the Chinese embassy, and Fawkes goes in to rescue him. It turns out the whole operation is a ploy to lure out the real American Invisible Man. Fawkes manages to escape with Bobby before they can drain the Quicksilver out of the gland, setting the place on fire.