"Knight and Day" has action by the boatload, cheeky wit, unexpected double-crossing, sexual tension, and the blinding smile of its star, Tom Cruise. In short, what more could you ask of a rollicking good-time movie? "Knight and Day", which also stars the irresistible Cameron Diaz as Cruise's superspy's ultimate foil, channels the best elements of earlier films like "Mr. and Mrs. Smith", "Mission: Impossible", the "Bourne" films, and even a little of "Duplicity"'s sophistication. Mostly, though, "Knight and Day" is about moving things along merrily, if not completely coherently, as the two stars tangle, and tussle with trust issues, in a completely believable, compulsively watchable way. Cruise plays Roy, an on-the-lam spy (who may have had some kind of psychotic break--or who may in fact be the only person telling the truth); he runs into the winsome June (Diaz), who gets caught up in Roy's mad dash to escape the cabal of federal agents on his tail. "No one follows us," Roy announces to a terrified diner crowd as he moves to make his escape with June, "or I kill myself--and then her." While "Knight and Day", directed by James Mangold, has more than its share of high-speed chases, hails of bullets, and explosions, it works far better as a romantic comedy--for the chemistry between Diaz and Cruise is delicious, palpable, and believable. So grab a date and an extra-large popcorn, and get ready for a sweet and fun "Knight and Day". --"A.T. Hurley"