Helen (Paltrow) loses her high-powered PR job and returns unexpectedly to her London flat to find boyfriend Gerry (Lynch) in bed with his ex Lydia (Tripplehorn). Or she doesn't. In some alternate reality, Helen is delayed, arrives home a few minutes after Lydia has left, and remains in the dark about the affair. Meanwhile, the other Helen - the one who walked out - finds a new life and a new admirer, a real charmer, James (Hannah). While touching on such perennials as the nature of destiny, fate and self-determination, this is essentially a romantic comedy with a nifty gimmick. As such, it's entertaining and smart. Although writer/director Howitt botches the dramatic fulcrum - the point where Helen's twin fates diverge - he pulls off the more difficult task of keeping both scenarios in the air with ease. The actors are crucial, none more so than the wonderful Paltrow, whose impeccable English accent is so precise it's disconcerting. Howitt might have pushed her harder to distinguish between the two Helens (she lets her hairdo do the work), but then this isn't meant to change your life - that's just a happy side effect.