Cruise plays Roy Miller, a CIA agent who claims to have been framed by his partner (Peter Saarsgard) for kidnapping a brilliant young scientist (Paul Dano) and stealing his new energy source, when he was really only protecting them from his sellout partner. Diaz plays June Havens, the owner of a garage that works on vintage cars, who is working on her father's old car as a gift for her sister (Maggie Grace), who is getting married. The two meet in Wichita, where Miller uses her to get the device through airport security, but when she ends up on a flight loaded with people trying to kill/capture Miller, the two are from that point on inextricably linked as the government and a Spanish arms dealer both try to get the invention back from him. The pursuit takes them from Boston to the Tropics to the Austria to Spain, but it's hard to sight-see when you're constantly involved in a high-speed chase.

With the exception of a couple of heart-to-heart talks between Miller and Havens about their hopes and dreams, which provide a nice break from things and establish that they are, in fact, soulmates or something, the movie is pretty much non-stop action. In fact, there's action that goes on off-screen that we don't even get to see, because whenever Havens gets knocked out (which happens a lot), we hilarously get flashes of what Miller is doing as he lugs her unconscious body around, and it makes us kind of sad we're missing it. The sequences are over-the-top in the best way possible, with Miller fighting a plane full of assassins, a highway full of feds, a warehouse full of gunmen, a compound full of goons and a street full of bulls. And each time (well, most of the time), he comes out on top, like he lives in the Matrix and he's The One: all his shots connect while he barely gets grazed, he can jump from car to car like he has suction cups on his feet, and he makes three guys vanish using only a bullwhip. (One assassin, gives him a tough time in a train car, but he appropriately meets an Agent Smith-like end.)

Cruise plays Miller like a roller coaster, looking introspective one minute and then raving like a madman, then shouting at Havens for a little while before charming the pants off of somebody. As hard as it is to separate his character from Cruise's personal life, you almost forget about his televised train wrecks while watching him do what he does best, which is pretty much what he always does -- run really fast, duck under crashing vehicles in tunnels, smile broadly -- but with a sense of humor. (Mel Gibson similarly played his iconic cop role minus the sense of humor earlier this year, in Edge of Darkness. Sadly, nobody saw it.)

The supporting cast is pretty impressive, and largely slumming it: Sarsgaard plays a serviceable bastard, Dano a sweetly mad genius, Viola Davis is cool as the CIA officer in charge, and Marc Blucas plays Havens' goofy fireman ex, who doesn't have much more to do than what we've seen a hundred times in the trailers. But Cameron Diaz is pretty awful. I'd love to blame the actress, but a lot of it is how her character is written: panicky and screamy and talkative at all the wrong moments, a talented mechanic and amateur boxer who turns into a six-year-old girl the minute someone shoots a gun anywhere near her. (Do people still find fear of guns funny? Haven't we all seen enough action movies to be ready for a female character who doesn't get hysterical when somebody pulls out a gun?) Her final-act transformation into a tough-as-nails killer is abrupt, but it's at least an end to all the screaming.

Even my biggest complaint going in, the randomness of the movie's title, is addressed -- Miller hides the device in a toy knight, and we also find out much later that that's his real last name. (Why couldn't "Knight" have been his cool code name and "Miller" his real name, instead of making the title a huge mystery? I have no idea.) But this movie could have been called anything, and I probably would have enjoyed it as much. Wichita, Trouble Man, Charlie's Angels 3, Mission: Impossible 5... it's all good in the hood.

Did you see Knight and Day? Let us know what you thought below, then get behind-the-scenes info from Tom Cruise's secret set diary!

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