KNIGHT AND DAY Breaking news: Tom Cruise is totally batshit.

LONG AGO in the annals of history—the 1600s, I believe—Tom Cruise and Cameron Diaz were pert, attractive stars of the cinema, spearheading big-budget Hollywood picture shows and charming their audiences with their clear complexions and adept skills at walking and talking. In the intervening centuries, however, both Cruise and Diaz have turned into gently defective androids laminated inside hot plastic. As for the walking and talking? They can manage, but not without inducing a wriggling feeling of discomfort in the audience—the same discomfort you might experience watching a crippled child cross a busy street, or a very expensive robot bump into a wall.

Some of this actually works in Knight and Day's favor, a movie whose entire plot hinges on the question, "Um, so Tom Cruise is totally crazy, right?" He plays the weirdly grinning Roy Miller, who kidnaps June Havens (Diaz) by claiming to be a secret agent on the run trying to protect both her and a perpetual energy machine from an evil FBI agent (a swollen-looking Peter Sarsgaard). June is terrified by Roy's obvious insanity whilst simultaneously smitten by his ability to assassinate dozens of feds as he creepily smiles and gazes into her eyes, repeating her name, "June," over and over again.

Considering Knight and Day's overcooked plot, it manages a fairly sophisticated sense of humor. Diaz is only mildly awful, and Cruise's performance succeeds because he doesn't play a human so much as cartoon character. The action is ludicrous, and the CGI is pretty terrible—a motorcycle chase amid the running of the bulls in Pamplona looks particularly crappy—but the movie rarely pauses to take itself seriously. At its best, it approaches the action-packed giddiness of Romancing the Stone or True Lies, and at its worst, it's still as entertaining as watching an expensive robot walk into a wall.