Here's the actual cause-effect chain of events as it would happen: Kate realizes that Alex is the dead guy, hit by the bus.
Kate writes him to warn him not to go and look for her, but to wait two years.
Alex does so to protect his life. Alex never gets hit by the bus.
Kate never sees the anonymous "guy" (Alex) get hit by the bus, so she never gets depressed by not being able to save him (she would have recognized him at the beginning of the movie as the "Alex" guy she kissed at her birthday party two years prior, anyway -- another ridiculous point that is never addressed) and never goes to the lake house to begin communication with Alex in the past.
Alex never gets to know Kate through that communication, so he is never in any of the places that we see him throughout the movie (the "walk" together around town with his little note at the end of it, the party, etc., and definitely not at the plaza on Valentine's Day.) By saving his life, Kate essentially would have instantly had no recollection of him or communication with him at all, and the entire thread of time-space would have placed her immediately elsewhere (probably with Morgan), totally oblivious of Alex's existence, and Alex would have gone on to form Visionary Vanguard with Henry, totally oblivious of Kate's existence.
Furthermore, if Kate and Alex never started their communication through the "time portal" mailbox, as the chain of events above states, Alex would have no reason to attend Kate's birthday party when he is invited after meeting Morgan when Jack runs away, as the name "Kate" would mean nothing to him. Thus, Kate and Morgan would never have moved into the lake house at any time in the past, so she would have no recollection of a lake house, much less a mailbox/time portal, much less Alex himself. She would have never known Jack, and the only interaction between ANY of them would have been Jack's running away to Morgan's front door, and Alex's brief, meaningless run-in with Morgan.
So Kate never would have sent any correspondence to Alex or anyone else through the lake house mailbox, so she would never have had to save Alex, but that's OK, because he wasn't there for the bus to hit. Cycle complete, happily ever after.
Overall, it was a typical Keanu Reeves BOMB. He hasn't had a good role since Bill and Ted's. And yes, that includes, in my opinion, The Matrix's "Neo." I'm surprised they got Sandra Bullock to play opposite him. Way beneath her intelligence level. "Speed" must have been a real good time for her.
To address the comments that proclaim ignorance on the behalf of the movie's critics who state its "implausibility":
It is not the fantastical nature of the plot overview, in that it attempts to incorporate time travel as a theme, that is repulsive to fantasy lovers, or that draws such harsh criticism.
Here's the problem that intelligence has with this film. The plot is not concerned with staying true to its own rules of cause and effect. It's that simple. Focused on drawing tears from young girls' eyes, it is a romance that completely forgets the logic of its own endeavor: When you make a movie about time travel (whether it's a person OR just messages through a mailbox), and you make changes in the past, it affects the future. You must consider holistic as well as fragmented causation, for the parts ultimately and linearly constitute a finished, although revised, timeline. You cannot cut and paste the changes it will make, you have to consider ALL of them. Movies like "The Thirteenth Floor," "The Butterfly Effect," and the "Back To The Future" series succeed where "The Lake House" fails in this regard.
Therefore, critics of this movie certainly may, without self-contradiction or cognitive dissonance, simultaneously praise fantasy for what it bold-facedly claims to be: fantasy. "Superman" does not violate its own established rules or step beyond its own paradigm to dumb down its audience with inconsistency. What is consistent at the beginning of the film(s) is consistent at the end. The same goes for the Lord of the Rings trilogy, The Neverending Story, Jumanji, Peter Pan, or a host of other fantasy/children's' movies that possess, and proudly boast of, a realm or occurrences that are otherworldly or imaginative. The complaint, once again, is not that fantasy has been attempted. The complaint is that the task of accuracy in the parameters of the cause-effect design has endured one of the following: careless neglect, complete omission, or incompetent butchery.
To repeat, the crime is not that the movie is implausible in scope, but in its outcome. The problem that the movie makers faced is that the outcome that they wanted, and that the audience wants, is incongruous with the outcome as it naturally unfolds according to the causation chain. Consequently and regrettably, they opted to make 2+2=13 or some such analogy.
In conclusion: Let fantasy be fantasy, but remember that it must, too, unconditionally obey its own individual and customized "non-negotiables," clearly set and understood by its audience, a group of rules for which time causation is the primary (and missing, or abducted) poster-child in "The Lake House."
Kate writes him to warn him not to go and look for her, but to wait two years.
Alex does so to protect his life. Alex never gets hit by the bus.
Kate never sees the anonymous "guy" (Alex) get hit by the bus, so she never gets depressed by not being able to save him (she would have recognized him at the beginning of the movie as the "Alex" guy she kissed at her birthday party two years prior, anyway -- another ridiculous point that is never addressed) and never goes to the lake house to begin communication with Alex in the past.
Alex never gets to know Kate through that communication, so he is never in any of the places that we see him throughout the movie (the "walk" together around town with his little note at the end of it, the party, etc., and definitely not at the plaza on Valentine's Day.) By saving his life, Kate essentially would have instantly had no recollection of him or communication with him at all, and the entire thread of time-space would have placed her immediately elsewhere (probably with Morgan), totally oblivious of Alex's existence, and Alex would have gone on to form Visionary Vanguard with Henry, totally oblivious of Kate's existence.
Furthermore, if Kate and Alex never started their communication through the "time portal" mailbox, as the chain of events above states, Alex would have no reason to attend Kate's birthday party when he is invited after meeting Morgan when Jack runs away, as the name "Kate" would mean nothing to him. Thus, Kate and Morgan would never have moved into the lake house at any time in the past, so she would have no recollection of a lake house, much less a mailbox/time portal, much less Alex himself. She would have never known Jack, and the only interaction between ANY of them would have been Jack's running away to Morgan's front door, and Alex's brief, meaningless run-in with Morgan.
So Kate never would have sent any correspondence to Alex or anyone else through the lake house mailbox, so she would never have had to save Alex, but that's OK, because he wasn't there for the bus to hit. Cycle complete, happily ever after.
Overall, it was a typical Keanu Reeves BOMB. He hasn't had a good role since Bill and Ted's. And yes, that includes, in my opinion, The Matrix's "Neo." I'm surprised they got Sandra Bullock to play opposite him. Way beneath her intelligence level. "Speed" must have been a real good time for her.
To address the comments that proclaim ignorance on the behalf of the movie's critics who state its "implausibility":
It is not the fantastical nature of the plot overview, in that it attempts to incorporate time travel as a theme, that is repulsive to fantasy lovers, or that draws such harsh criticism.
Here's the problem that intelligence has with this film. The plot is not concerned with staying true to its own rules of cause and effect. It's that simple. Focused on drawing tears from young girls' eyes, it is a romance that completely forgets the logic of its own endeavor: When you make a movie about time travel (whether it's a person OR just messages through a mailbox), and you make changes in the past, it affects the future. You must consider holistic as well as fragmented causation, for the parts ultimately and linearly constitute a finished, although revised, timeline. You cannot cut and paste the changes it will make, you have to consider ALL of them. Movies like "The Thirteenth Floor," "The Butterfly Effect," and the "Back To The Future" series succeed where "The Lake House" fails in this regard.
Therefore, critics of this movie certainly may, without self-contradiction or cognitive dissonance, simultaneously praise fantasy for what it bold-facedly claims to be: fantasy. "Superman" does not violate its own established rules or step beyond its own paradigm to dumb down its audience with inconsistency. What is consistent at the beginning of the film(s) is consistent at the end. The same goes for the Lord of the Rings trilogy, The Neverending Story, Jumanji, Peter Pan, or a host of other fantasy/children's' movies that possess, and proudly boast of, a realm or occurrences that are otherworldly or imaginative. The complaint, once again, is not that fantasy has been attempted. The complaint is that the task of accuracy in the parameters of the cause-effect design has endured one of the following: careless neglect, complete omission, or incompetent butchery.
To repeat, the crime is not that the movie is implausible in scope, but in its outcome. The problem that the movie makers faced is that the outcome that they wanted, and that the audience wants, is incongruous with the outcome as it naturally unfolds according to the causation chain. Consequently and regrettably, they opted to make 2+2=13 or some such analogy.
In conclusion: Let fantasy be fantasy, but remember that it must, too, unconditionally obey its own individual and customized "non-negotiables," clearly set and understood by its audience, a group of rules for which time causation is the primary (and missing, or abducted) poster-child in "The Lake House."