Alfred Hitchcock famously distinguished between "surprise" and "suspense". If a bomb goes off without forewarning, that's surprise. If we, as an audience, are tipped off in advance that the timer is running and that the bomb will explode at precisely one o'clock, that is suspense.
The Spanish director Jaume Collet-Serra and his writers Chris Roach and John Richardson take a very literal approach to Hitchcock's definition of suspense. Again and again in the fitfully entertaining but wildly manipulative Non-Stop, we see stopwatches being set.
Again and again, we are warned that catastrophe is imminent. "In exactly 20 minutes, I am going to kill someone on this plane," the unknown villain tells us in a text. That is only the first of the timed warnings that are dotted throughout the movie.
The film-makers borrow randomly from 1970s disaster movies and from pot-boiling, Agatha Christie-style whodunits. You sense that they've been through a thorough checklist of plot elements and character types before the plane has even been allowed to take off. Yes, there is a doctor aboard. Yes, among the passengers is a doe-eyed little girl hugging a teddy bear. Poison? Yes. Bomb? Yes. Airplane captain flirting with glamorous flight attendant? Yes. Parachute? Yes. Couple having sex in business class? Yes. Turbulence? Yes. People vomiting and dying because of eating airline food? No.
Non-Stop is not a film that will appeal to the airline industry. In its lesser moments, it seems like just another crudely mechanical and increasingly preposterous thriller set during a particularly hellish plane journey. However, true to the title, it does indeed strike a relentless narrative tempo. There are at least hints that Collet-Serra is trying to push beyond the genre's conventions.
It helps that the 61-year-old lead, Liam Neeson, has a gravitas and a brooding sense of melancholy that younger action stars often lack. Just so we know that he is on the washed-up side, he is shown here early on stirring his paper cup of whisky with his toothbrush. His character, Bill Marks, is a US Air Marshal who has been traumatised by a family tragedy. Marks has taken to drink, is full of self-pity and (somewhat ridiculously, given his job) has an acute fear of flying. Initially, he seems closer to Ray Milland in The Lost Weekend, Billy Wilder's famous 1945 drama about alcoholism, than he does to Jason Bourne.
Collet-Serra, who also directed Neeson in Unknown, sets up the film in intriguing fashion. We see the hungover Marks making his way on to the plane, eyeing up fellow passengers, who come in all ages and all guises. He is expecting a routine flight and even makes small talk with Jen Summers (Julianne Moore), a glamorous but aloof woman whose yearning to sit in a window seat seems suspicious.
When it all gets too much for Neeson, his default behaviour is to lock himself in the bathroom and have a fag. At times here, we half suspect that he might be as delusional as the insomniac office worker in David Fincher's Fight Club, an Air Marshal seeing phantoms where none exist. Even more intriguingly, there are moments when Neeson doesn't seem quite sure whether he is the hero or the villain. "Control is an illusion," he is told by his antagonist. Crossing the Atlantic with a maniac in their midst, 40,000 feet in the air, he and the passengers crammed into the plane are powerless to influence events.
It is a testament to Neeson that he is able to give us so much sense of his character's inner life in an action movie that is otherwise so one-dimensional. He has a wounded-lion quality as he blunders up and down the aisles.
The rest of the cast have largely thankless and underwritten roles. Michelle Dockery is a doughty, quick-thinking flight attendant. She at least has a few lines of dialogue. That's more than her fellow attendant Lupita Amondi Nyong'o, so striking in 12 Years a Slave but shamefully underused here. It is likewise a mystery as to why an actress as accomplished as Julianne Moore would take a role as skimpily written as the one she has here.
There are fleeting references to 9/11 and the terror it unleashed in the American public. Not that Collet-Serra wants to probe too far into the politics of fear. This is ultimately a fairground ride of a movie in which the aim is to excite and terrify audiences, not to provoke too much thought.
Thanks to the cryptic but threatening text messages he has been receiving on his secure phone, Neeson knows that his Moriarty- like adversary is on the plane, probably sitting only a few feet from him. One of the pleasures of the film is the Cluedo-like game of trying to identify the villain. It could be anybody.
Some of the action scenes are very cleverly handled. There is a tremendous fight sequence in the tiny airplane bathroom, where space is so tight that it is barely possible to even throw a punch. The film-makers play up the claustrophobic settings as much as they do the time constraints.
"It doesn't make any sense," Neeson's character laments as he struggles forlornly to work out his adversary's motivation and behaviour. The remark could just as well apply to the plot, which becomes increasingly absurd the further the flight progresses.
Then again, there is no reason why suspense movies need to be logical or coherent. All they need is a bomb under the table (or in the overhead locker) and plenty of advanced warning that it is going to go off... unless Liam Neeson saves everyone first. Neeson's emergence so late in his career as one of contemporary cinema's most bankable tough guys may be surprising but he certainly can't be accused of skimping his action-man duties here.