In London, Okwe (Chiwetel Ejiofor) is an undocumented alien from Nigeria who works as a cabbie and moonlights as a hotel attendant. He shares living quarters with Turkish émigré Senay (Audrey Tautou). Working late one evening, Okwe is called up to one of the hotel suites. Inside, he finds a prostitute standing by a toilet that's clogged with a human heart. This leads him to the hotel manager (Sergi López), and he soon uncovers a darker side to his employer and his adopted city.