Filmmakers have been looking for an excuse to reunite Sandra Bullock and Keanu Reeves ever since their fateful kiss on the danger bus in 1994’s “Speed.” While their chemistry in “The Lake House” may not be as dynamic as the crash-and-burn romance in that film, the pairing of these two American sweethearts has an undeniable appeal.

But while skeptics who may have written off “Speed” as just a “bus movie” were proven wrong by the film’s overwhelming success, those who are hung up on the premise of “The Lake House” have a more reasonable grievance.

Dr. Kate Foster (Ms. Bullock) and Alex Wyler (Mr. Reeves) have never met,but they have both been tenants at a beautiful glass lake house near Chicago. It turns out that Kate and Alex are perfect for each other, but time has played an evil trick on them – putting them in the same place, but he in 2004 and she in 2006. Luckily, they can easily breach this divide through the use of a *magical mailbox*.

When Kate contacts him with a routine note in the mailbox, it becomes clear that they are living in different years. Their notes can traverse through time when placed inside the box, allowing them to communicate through lovelorn letters. Naturally they start up a romance.

Much like slow-burn romances from years gone by,where couples have been separated by an ocean or forced apart by a war, the two begin to cherish their communiques; slowly falling in love.

The appeal of squirreled away love notes and delayed satisfaction may be apparent, but it seems a gross miscalculation to set this film in the modern world. Sadly, with the omnipresence of global communications, there is almost no way to recreate the rose-colored correspondence of years gone by. In comparison to the romantic love letters that past generations could show their grandchildren, emails and instant message conversations just don’t have the same charm. Perhaps director Alejandro Agresti and writer David Auburn were trying to learn a lesson from a film like 1998’s “You’ve Got Mail.”

“The Lake House” tries to sidestep that issue through their supernatural postbox, but the trick is just too cheap to ignore. And it is a shame, since Ms. Bullock and Mr. Reeves do make such a great onscreen pair.

Despite his deadpan delivery and seeming dullness, Mr. Reeves is a beautiful man. He is beginning to grow out of his boyish surf boy charms, but he sparkles with Ms.Bullock at his side.Mr. Reeves is at his best playing characters without terribly demanding personalities, and the architect Alex doesn’t have too many traits that get in his way.

But it is Ms. Bullock that makes big strides toward making the film work. One of America’s last true sweethearts, Ms. Bullock is known more for her easy laugh and neurotic whimsy than her acting skills, but this is a role that utilizes her natural virtues. She is at ease as the romantic lead, and looks to have outgrown some of her more irritating tendencies. Her Kate is a charmingly short-haired version of the standard Sandra Bullock prototype.

But her charming performance is not enough to overcome the film’s premise, or how quickly the writers abandon their own rules to propel the story line. The two lovebirds live in and around the same city, but two years apart. Occasionally they taunt the time-space continuum by trying to meet up in the past or future, to confusing results.Also, to move the action along, the script occasionally allows them to have conversations through voiceover instead of waiting for the tedious back and forth of letter writing. And their magical postman seems to be unreliable, as some letters arrive much sooner than others.

And while the creators of “The Lake House” did manage to incorporate a deadly bus into their script, the delayed revelation of that crash is unforgivably predictable and tedious.

The pairing of these two American sweethearts has proven successful at the box office before and watching them romance each other here may well prove to entice viewers. But it is a sad fact of modern life that the filmmakers felt they had to resort to a hole in the time-space continuum to tell this tale of unrequited love.