Adapted by Stuart Beattie from James Siegel's novel, Derailed is the story of how fatigue and unsuspected neediness can distract you and change your life almost in an instant. Charles and Deanna Schine would seem to have it made, but people seldom really do, and the Schines most certainly don't. Even the exceedingly prosperous often live on the edge of a bluff from which they can tumble for a variety of reasons. Early scenes establish their shared vulnerability. Deanna's principal has an annoying habit of dropping into her classroom when she isn't following the school's dictated lesson schedule. Charles' major client has decided he's too independent and no longer wants him assigned to her account. Meanwhile, the Schines' beloved teenage daughter Amy (Addison Timlin) has an aggressive form of diabetes, and her treatment is costing her parents tens of thousands of dollars a year.
Pursuing their careers and sharing parental care for Amy has left the Schines exhausted and with too little time and energy to devote to each other. Then, Charles meets Lucinda Harris (Jennifer Anniston, who gives still further evidence that she's the member of the Friends cast with the true big-screen chops), a fellow commuter on his daily train to the Loop. She kindly buys his ticket one day when he boards the train with an empty wallet. They talk. She's an investment banker and parent of a daughter, too. They recognize in each other that same weariness from the grind of professional life, and though neither states the fact directly they each intuit that the other is mired in a marriage that has lost its spark.
The movie is very smart in this regard. Lucinda is a beautiful woman, but no more so than Deanna. Thus, Charles is drawn to Lucinda not purely out of physical lust but because Lucinda is willing to focus her attention on him in a season when Deanna has fallen out of the habit of doing so.
Charles and Lucinda meet for a drink, and, one foot out on the slippery slope of betrayal, they go sliding out of control into a movie pretty different from the domestic drama we thought we were watching. When Charles and Lucinda retreat from a chi-chi bar to a seedy hotel, they are brutally attacked by an intruder. Charles is beaten, and Lucinda is raped. But in the aftermath of their violation they can't go to the police lest their spouses learn what they were up to. Realizing that they haven't reported his crime, the attacker, Laroche (Vincent Cassel), who knows their identities from the wallets he's stolen, begins a campaign of blackmail.
The set-up is executed perfectly. We possess feelings for our three leads -- Charles, Deanna and Lucinda (we don't meet her husband) -- wishing them all a way out of a tangle of their own making. Lucinda delivers a revealing line when she tells Charles about his boss, "Some people just don't know how to appreciate what they've got," an insight that has much wider applications than she intends. And like a twisting rollercoaster, the picture keeps us nicely off balance, whipping us through as many unexpected moments as a two-hour flick can deliver. Will Laroche be satisfied with his blackmail cash? Will Charles follow through on his idea of getting his ex-con friend Winston (RZA) to intimidate Laroche? Can Charles and Lucinda conceivably keep their spouses from learning of their interrupted infidelity?
Looking backwards, we see that some of the film's developments are contrived. If seemingly inconsequential events don't occur exactly as they do, subsequent essential events couldn't have been orchestrated at all. And I fear that veteran moviegoers will see some things coming simply because they've been to so many movies and they've learned that a primary rule of thrillers is to trust nothing. My wife and I separately guessed the film's biggest revelation a half hour early. There are plenty of developments you won't and can't predict, however. And the picture proves entirely diverting while you're in the theater.