Given the ludicrous nature of the concept Dowling and Ray's script does an impressive job.
The story begins in Germany soon after the husband of Kyle Pratt (Jodie Foster) is killed in a fall. Kyle and her six year old daughter Julia (Marlene Lawston) leave Germany to fly to America. Or do they?
Three hours into the flight Kyle wakes up to find that Julia is missing. So is Julia's luggage, her boarding pass and every trace of her. None of the passengers or crew remember her boarding. It's a case of "The young lady vanishes".
Kyle is, of course, determined to find her daughter. But was she ever on board? Is Kyle suffering from delusional grief? Does Julia even exist?
The script has fun ringing the changes on these possibilities. The atmosphere of paranoia and suspicion is enhanced nicely by Schwentke's tense direction. Flightplan makes good use of its post-911 credentials.
In terms of acting this is Jodie Foster's film and probably wouldn't have worked without her. She does a great job as the distraught and possibly deranged mother who will stop at nothing to save the daughter she believes has vanished. Yes, her performance is melodramatic and has only one gear - but that suits the role. Support is competent with Peter Sarsgaard smugly irritating as the air marshal and Sean Bean well cast as the pilot.
Ultimately, of course, once the script has explored all the limited possibilities of the scenario it has to make a decision as to which way to go. When the reveal came it was both disappointing and obvious. However despite this the last act still manages to maintain interest.
Which is good because otherwise you'd notice the glaring plot holes. The story is frankly nonsense, however it's told very well. So well that you can - almost - ignore the implausibility of the whole thing.
So the end of the film is nowhere near as good as the beginning - I wondered if that's connected with having two writers? - but is still fun in a different way.
Flightplan is a movie that shouldn't have worked but did. Just try not to listen to the music near the end.
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