'Love and Other Drugs'

Much hype has been created over the casting of the romantic drama 'Love and Other Drugs' (opening Nov. 24), which reunites Jake Gyllenhaal and Anne Hathaway for the first time since they played an unhappily married couple five years ago in 'Brokeback Mountain.' The hype underscores the curious fact that Hollywood's leading men and leading women rarely appear together more than once.

It has not always been so. In old Hollywood, if a screen couple clicked, they'd appear together numerous times, like Spencer Tracy and Katharine Hepburn (who made nine movies together), Myrna Loy and William Powell (who made 14 movies together, including the six 'Thin Man' titles) or John Wayne and Maureen O'Hara (five movies together). Even as recently as the 1990s, you had Tom Hanks and Meg Ryan (three movies) and Julia Roberts and Richard Gere (two movies). So why doesn't Hollywood reuse couples anymore?

There are a couple of possible reasons. One is chemistry. How many screen couples in the last few years have sparked such combustible chemistry that you'd actually want to see them together again? Kevin Spacey and Kate Bosworth have made three movies together -- quick, can you name any of them? Want to see them make a fourth?

Over the last two decades, even real-life couples who acted together more than once (think Tom Cruise and Nicole Kidman, or Alec Baldwin and Kim Basinger, or Ben Affleck and Jennifer Lopez) have had difficulty translating their off-camera romances to the big screen. (Then again, considering that those couples didn't last, maybe their lack of movie chemistry should have told us something.) None of them have lit up the screen the way real-life couples of yesteryear did, like Tracy and Hepburn, or Humphrey Bogart and Lauren Bacall (who co-starred four times), or even Woody Allen/Diane Keaton and Woody Allen/Mia Farrow.

Even when there is chemistry, lightning doesn't always strike twice. Kate Winslet and Leonardo DiCaprio were smoldering in 'Titanic,' but in 'Revolutionary Road' a decade later, not so much. Adam Sandler and Drew Barrymore seemed an effortlessly well-matched couple in 'The Wedding Singer,' but in '50 First Dates' they seemed to be trying too hard to recapture the magic. Is there anyone who prefers Keanu Reeves and Sandra Bullock in 'The Lake House' to Reeves and Bullock in 'Speed'?

The other reason, however, has to do with the way romantic movies are written nowadays. Which is: poorly. It's rare to see a romantic comedy or drama where the man and the woman are both fully rounded characters, with dreams, goals, foibles, idiosyncrasies. Usually, one is the protagonist and the other is a caricature, or a projection of the other one's desires and fears. It's not like the supposedly bad old pre-feminist days, in the Hollywood of Hepburn and Cary Grant (three movies together), when romances were written as matches of equal partners, men and women who both gave as good as they got. Given the inability of today's screenwriters to write more than one vivid character per movie, it's no wonder that it's hard to get two high-powered stars to agree to be in even one movie together, let alone two or more.

That said, there are some pairs who've worked together well on more than one or even two occasions. Richard Gere and Diane Lane are smooth pros who've played very different pairs in three films over the last 30 years ('The Cotton Club,' 'Unfaithful' and 'Nights in Rodanthe'). Tim Burton has paired his favorite leads, the chameleonic Johnny Depp and Helena Bonham Carter, four times (though they didn't have any scenes together in 'Charlie and the Chocolate Factory').

Other couples barely registered the first time, so their second projects together are more like a do-over. That includes Gyllenhaal and Hathaway, who didn't have much screen time together in 'Brokeback Mountain' (where Gyllenhaal's primary love interest was, of course, Heath Ledger). Sean Penn and Naomi Watts' portrayal of a beleaguered Washington power couple in 'Fair Game' is so compelling that it makes one forget their work in '21 Grams' -- or it would, if anyone had seen that. And Paul Rudd and Reese Witherspoon are about to reunite in next month's 'How Do You Know.' What, you didn't see their 1998 romantic comedy 'Overnight Delivery'? Trust me, they were cute together in that. Maybe they will be again.

•Follow Gary Susman on Twitter @garysusman.

Related: Best On-Screen Romantic Reunions
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