The box office performance of a "high concept" film such as Snakes on a Plane is typically based not on the cleverness of the concept but on whether there is actually a good movie in it. Die Hard and Speed, for example, had characters we could care about, and the films put them in situations where they had interesting choices to make. Those that don't have these things usually fall off at the box office even if they get a good opening weekend.
Interestingly, the least entertaining and involving parts of Snakes on a Plane are the two big action scenes in which the serpents attack the passengers on the plane. The snakes operate in a riidiculously implausible manner, even if we accept the filmmakers' premise that pheromones released on the plane would make the creatures more aggressive. These snakes are much more than "more aggressive"; they're positively malevolent and volitional. That's not at all believable—and it's not the slightest bit necessary, for the film is interesting enough without sci-fi snakes.
The first 40 minutes of the picture are devoted to scenes setting the stage for the big action sequences. The central conceit is that a young man who witnessed a murder by a powerful gangster in Hawaii consents to testify against the killer and is duly to be flown to Los Angeles to appear in court. That leads to the scheme to release hundreds of snakes on the plane and cause it to crash. OK, better plans have been devised in this world, but we'll let it go, shall we?
After all, what really makes a high-concept thriller successful is how the characters react to the situation, and especially the need for them to show courage, honor, and other good character traits. Snakes on a Plane has plenty of that, with some characters acting honorably, others meanly, and others developing better character through the course of the story. What is most pleasing is that the characters actually manage to surprise us just a little bit once in a while. The film has a solid performance by Samuel L. Jackson at its center, and it has the right amount of humor, meaning not too much. Snakes on a Plane also has enough action-film cliches to choke an anaconda, but the filmmakers' willingness to let us see human character in action makes it worth seeing.
From Karnick on Culture.