Lu Fan is a city office worker who has always seen herself as thoroughly ordinary, until an alien claiming to come from Saturn abducts her. He gives a ridiculous explanation for invading Earth, and his plan hinges on getting Lu Fan to fall in love with him and then turn against her own planet. Her daily life with the Saturnian quickly becomes comic, and visitors from other planets keep turning up around her, each with goals of their own, their paths tangled together in Beijing. As Lu Fan slowly falls for the Saturnian and begins to suspect she is not so ordinary after all, she faces a choice between him and Earth. The result is a romantic comedy with a science fiction twist and some dramatic weight.