It's always fun to see a filmmaker use the chilly ''inhuman'' surface of modern city landscapes as a ready-made stage set for a science-fiction fantasy. Jean-Luc Godard more or less pioneered the technique in 1965 with ''Alphaville'' (other examples have included ''A Clockwork Orange,'' David Cronenberg's 1970 ''Crimes of the Future,'' and ''Gattaca''), and Michael Winterbottom makes his contribution to the genre in the ingeniously designed and photographed Code 46. It's not that the film is devoid of fanciful special effects -- a window-projection TV here, a video cell phone there -- but that Winterbottom, the eclectic British stylist (''24 Hour Party People,'' ''The Claim''), turns the highways, skyscrapers, and office spaces, the dun-colored grandeur of contemporary Shanghai, into an ominously plausible global nexus of the not-so-distant future.
Into this vaguely fascist megalopolis comes William (Tim Robbins), an insurance-fraud investigator who has been knowingly infected with an empathy virus that allows him to read people's thoughts. As soon as he interviews Maria (Samantha Morton), he realizes she's the corporate outlaw who has been smuggling fake ''papelles'' (they're like passports) out of the company she works for. Instead of turning her in, he falls in love with her. Robbins and Morton make a sexy and moving pair of desperadoes; you mourn their every loss. ''Code 46'' has a noirish fatalism that renders it a close cousin to ''Blade Runner,'' but Winterbottom's film, shot mostly in the light, uses the theme of memory erasure to peer into the eternal sunshine of tragically altered minds.