Thirty-odd minutes into Knight and Day, the action-comedy concoction from director James Mangold (3:10 To Yuma, Identity), and things are looking surprisingly good. Tom Cruise oozes charisma, Cameron Diaz has pizazz. The story has me guessing, the action has me smiling. “This is great!” I say to myself, almost prepared to call this one of the more entertaining Hollywood blockbusters of the year so far.

Then, out of nowhere, tragedy strikes; the film hits the proverbial iceberg and starts to fall apart. The narrative springs a leak. The humour mill runs out of steam. The action grows weary, the star chemistry goes cold. Within a matter of minutes, Mangold’s film has sunk deep into the abyss of mediocrity.

Now, before I start playing the blame game, allow me to start from the beginning.

The Hitchcockian setup goes something like this: June Havens (Diaz) is a quirky car mechanic who repeatedly bumps heads with the ever charming Roy Miller (Cruise) while on her way through airport security. Of course, there’s more to their encounters than meets the eye; Roy is actually a top secret agent who, according to CIA Director Isabel George (Viola Davis), has recently gone rogue. He has apparently stolen a device codenamed ‘Zephyr’, something that the agency would very much like to have back in their possession. But what exactly is the Zephyr? Why has Roy stolen it? Whose side is Roy on? And what has June got to do with anything?  These questions are what make the first 30 minutes so damn intriguing.

Naturally, Roy and June end up boarding the same flight and continue their flirting, but before they get a chance to join the Mile-High club (did I mention Cruise oozes charisma?), a bunch of gun-wielding, agency-type assailants jump from their seats and try to take out Roy. The resulting mid-air shootout is edgy, funny and clouded in more question-raising mystique. It’s everything the film that follows is not.

I can pinpoint the very moment things take a turn for the worse. It happens when Patrick O’Neill’s screenplay starts to answer all the big questions with disappointing explanations, sucking dry all the mystery and novelty that made for such an engaging setup. Consequently, no new questions arise to help propel the film forward, causing the remaining glut of action scenes to come across as meaningless, unremarkable and just plain dull. To make matters worse, Mangold uses this time-cutting technique that sees Roy drug June– and by extension, the audience – into a deep sleep so that when she awakens a few days later, she’s in a different location, wearing a different outfit and ready to be involved in a different shootout. It makes for an amusing narrative device the first time around, but it’s overused to the point where the entire film becomes one hazy, overlong action scene spread across multiple continents for what appears to be no reason at all. And what’s with the title Knight and Day? It only makes a fraction of sense.

To be fair, not all of the film’s initial appeal is lost in the wreckage. The glue holding this shambolic film together is, without a doubt, Tom Cruise. Put aside any reservations you have toward his personal life and there’s no denying the man can act. In an age where big CGI effects are all that it takes to rule the box office, Cruise has that classic star magnetism capable of carrying a film that is otherwise without legs. Diaz also doesn’t disappoint as June, successfully countering Cruise’s boundless charm with her perpetual state of bewilderment. It’s a shame, however, that the sexual tension and humorous banter that made the first half so entertaining is later restricted to a few instances of rapid wordplay and a couple of seductive smiles. Yet with all the hullabaloo happening around them, that’s about all they have time for.

Sure, you can thank Cruise and Diaz for partly salvaging the second half of Knight and Day, but the fact is the boat still sinks. It’s a truly sad sight to watch all that initial promise go so astray, especially when this is one of the few original big-budget films to come out of the franchise-driven Hollywood movie machine. What’s not so original is that it belongs to increasingly popular action-comedy genre, already inundated with new members such as Cop Out, From Paris With Love, Iron Man 2, Kick-Ass, The Losers and The A-Team. All of these, bar Cop Out, are more accomplished films than Knight and Day, blending the humour and thrills with more consistency and style than James Mangold does here.

But wow, those first thirty minutes sure were something…

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