Adam Raki (Hugh Dancy), an electronics engineer, has an autism disorder called Asperger syndrome. When a young woman named Beth (Rose Byrne) moves into his apartment building, he is quite taken with her. She does not quite know how to react to Adam's unconventional overtures but decides to give him a chance nonetheless. But Beth's parents are apprehensive about her new romance, which could end the young lovers' relationship before it has a chance.