In Stephen Frears's Dirty Pretty Things, Okwe (Chiwetel Ejiofor), an undocumented Nigerian immigrant in London, works as a cabdriver by day and as a deskman at an hourly-rate hotel by night and still can't make ends meet. He chews a stimulant leaf to stay awake for unnaturally long stretches and when he needs to sleep crashes on a couch he rents from Senay (Audrey Tautou), a chambermaid at the hotel who is an immigrant from Turkey with a visa that doesn't allow her to work or to take money from a lodger. When immigration agents, acting on a tip, bust in on her, Okwe leaps out the window barefoot. When they show up at the hotel to catch her arriving for her shift, she has to flee and sinks even lower in the service economy to a job in a garment sweatshop. The agents then raid that looking for her, after which the boss has leverage to demand sexual favors.

Okwe was a physician in Nigeria (before being driven into political exile), so his cab dispatcher asks him to diagnose a urinary pain. It's the clap and the man then presses Okwe to procure some amoxycillin for him which he gets from Guo Yi (Benedict Wong), a chess buddy who works as a janitor in a hospital morgue. Okwe won't accept payment for these services. He's the movie's overmatched white knight, moving through the cityscape of immigrant torment doing the little good he can and grieving over the rest.

In the establishing sequence, Juliette (Sophie Okonedo), a pop-up valentine of a hooker and a regular patron of the hotel, stops to flirt with Okwe and inform him of a problem in her room. (With Juliette you can't tell if the flirtation is incidental to reporting the problem or vice versa.) Investigating, Okwe discovers a human heart stopping up the toilet. Okwe tells the manager of the night staff about it, but Senor Juan (Sergi Lopez) both threatens and attempts to bribe him to forget about it. Sensing something nefarious, Okwe plays detective and uncovers a horrible open secret: illegal immigrants deliver up a kidney in unsanitary operations in hotel rooms in return for expertly forged papers. (The kidneys are carried immediately to the hotel parking garage on ice in the same styrofoam containers in which truffles are flown in from Provence and gross Senor Juan 10,000 pounds sterling apiece.)

The Mephistophelean Senor Juan doesn't try to snuff Okwe to protect this gruesome, predatory business, he tries to hire him as a more proficient surgeon. But Okwe is incorruptible. In fact, he has no flaws at all and even says of himself that he doesn't want to do anything to harm anybody. Thus, what seems at first to be a naturalistic look at the desperation and exposure of immigrants turns into melodrama. By time Senay decides to give up a kidney to Senor Juan (who fucks her as a sort of finder's fee) and Okwe the incorruptible turns the operating tables on the smirking blackguard, anything distinctive about the movie has fallen away.