AMANDA and STEVE have been together since college… and Amanda has had enough! She’s a hard-working businesswoman - he’s a lazy hypochondriac. She has a high sex drive - he brings his Playstation to bed. Her plan to dump him, however, is interrupted by the news that a non-lethal virus is rapidly sweeping through the male population of the planet, incapacitating men of all ages with severe flu-like symptoms. All, that is, except for Steve, who turns out to be immune to the virus. So, Amanda suddenly finds herself with the fittest boyfriend on the planet!
Amanda confides in her best friend Sara about her healthy boyfriend, swearing her to secrecy. Soon every woman in London knows about him, and Amanda and Steve are forced to go on the run; deciding to head for Scotland where Steve’s ex-girlfriend, a famous immunologist, may be able to create an antivirus from a sample of Steve’s blood. And so, with Steve disguised as a woman, the couple flees London, amidst wide-spread looting of shoe shops and with gangs of heavily armed desperate housewives, lonely single women, and militant feminists roaming the streets, hunting for the now legendary Steve. Steve is forced to embrace his feminine side, and with a new-found perspective comes to realize how much he’s taken Amanda for granted.
Can Amanda and Steve save their relationship, and in the process, mankind?