There will be a lot of people who will describe "Flightplan" as "Panic Room" on a plane, and the comparison isn't exactly unwarranted. Both, of course, star the incomparable Jodie Foster, both are claustrophobic thrillers set primarily in a closed-up space, and both put she and her young daughter in danger. Why Foster, who recently has only been making a major film every two or three years, would want to repeat herself is anyone's guess—she is one of cinema history's great talents, and capable of more diverse roles—but that doesn't mean she is sleepwalking through the role. Quite the contrary, Foster puts all her energy every inch of her being into the film, producing another masterstroke of a performance that is filled with breathless emotional range, poignant vulnerability, and admirable strength.

Surrounding Jodie Foster's tour de force turn is a frequently slam-bang mystery-thriller that ends up being much less than the actress' equal, but is still a solid armrest clencher for most of its running time. Following the abrupt falling death of her husband, Kyle Pratt (Jodie Foster), with six-year-old daughter Julia (Marlene Lawston) in tow, leaves her home in Berlin to take the body back to New York. Upon waking up from a nap on the massive, top-of-the-line commercial airplane that she, an aeronautics engineer, had a hand in making, Kyle discovers that Julia is missing. Upon scouring the plane and coming up with no trace of her, Kyle comes to the conclusion that someone onboard must be hiding her. As tensions rise, the passengers state that they never saw her with a little girl, and the crew claim that Julia isn't listed on their manifest, Kyle's sanity is put into question. Did she imagine her daughter was with her, or is it all a part of an expertly concocted conspiracy?

Fluidly directed by Robert Schwentke, "Flightplan" is the second airplane-set suspenser in a month's time, and, if not matching the airtight plotting and more consistent success of "Red Eye," it still brings to the table its fair share of thrills. The film immediately sucks the viewer in with its gradual, smartly constructed set up and ultimate conundrum of where Julia is—if she even exists at all. Helping to keep one enthralled is the wise decision to keep attention solely on Kyle's frightening plight. Save for some unnecessary, over-the-top dealings with the other passengers that should have been downplayed or discarded (the clapping scene is just silly), the picture stays on track, and Foster's earnest portrayal of Kyle leaves one with a genuine rooting interest in getting to the bottom of the central mystery.

What appears to be setting itself up as a more existential tale about loss and the human process of grieving—Kyle is grappling with the tragic loss of her husband when she is faced with the possibility of also losing her only child—eventually dissolves into a more routine, action-oriented picture that could have amounted to much more than it does. Because the trailers and television ads seemingly gave too much away, it was natural to expect that screenwriters Peter A. Dowling and Billy Ray (2004's "Suspect Zero") would have more tricks up their sleeve than meets the eye, but they really don't. When what is really going on is revealed, it comes as an unimaginative anticlimax that just about anyone could guess before setting foot in the theater. Even if the third act disappoints from a subjective standpoint and is a little wobbly on its feet, there is still a tautness in the filmmaking and Foster's front-and-center performance that helps to iron out many of its misgivings.

Joining Jodie Foster are a slew of fine actors in second-tier roles. The intense Peter Sarsgaard (2003's "Shattered Glass") plays air marshal Gene Carson, a man who is skeptical of Kyle but sympathetic to what she is going through; Sean Bean (2001's "The Lord of the Rings: The Fellowship of the Ring") is flight captain Rich, who initially agrees to help Kyle in her search; and Erika Christensen (2005's "The Upside of Anger") is flight attendant Fiona. Christensen no doubt took the part for the chance to work with Foster—who wouldn't?—because there's no way she would have otherwise agreed to such a thin and thankless role.

The final scene of "Flightplan" puts a slight damper on what has come before, becoming so sentimentally treacly that it will satisfy only those who liked the ludicrous ending of the otherwise astounding "War of the Worlds." The out-of-left-field gesture of kindness that a key supporting character gives Kyle in the last shot rings especially false and, unfortunately, produces a bad laugh. What comes before this, though, is assuredly tense and serious enough that the culminating flaws do not sink the project. With seamless camerawork by Florian Ballhaus a mesmerizing character all its own, and the production design of the sprawling, multileveled airplane brilliantly conceived, "Flightplan" is a more style than substance affair, but one that is always entertaining and occasionally electrifying. Where the flight from hell leads is no great shake, but getting there is exciting enough to be worth the trip.