This was only playing at one cinema in my area (off my usual track) and when I saw it listed in the paper I thought "Wait, how did I miss that?" But it was rated R (always a plus for me; for one thing, an R rating means the F-word gets used at least twice, so it'll have at least that much realism) and I had read somewhere (probably on IMDB) that it was about submarines, so I thought I'd take a crack at it. My venture was well rewarded.
Set during World War II, an American submarine rescues 3 people on a liferaft, one of whom turns out to be a woman, news of which galvanizes the sub's crew, who seem to know every female slang term ("Brillo pad" was new to me). The movie pays tribute to the German "Das Boot," the best submarine flick ever, as the camera goes darting from one passageway to another as the crewmen are introduced. Then some odd things start occurring.
Helping to win me over was the sheer copiousness of period detail with all the 1940s technology used by the crew to run their boat plus their cigarettes, girlie pin-ups, phonograph records, a Yo-Yo, etc. The actors all rang true except for the young idealistic guy. Lots of great claustrophobic atmosphere; limited but effective use of a certain kind of special effect. One needs to pay attention, such as the mirror scene, where you might think "Is that image duplicating what the guy is doing, or not?" Slow but steady heightening of tension and development of otherwordly aspects. Delightful underwater renditions with plankton & manta rays cavorting. Some drawbacks: too much use of flashbacks, some of which may be "false" (Hitchcock used a false flashback once & always regretted it); too much action occurring off-screen, to where it calls attention to itself. There's a central flashback issue that seems to call for an awful lot of expository dialogue, some of which occurs when one would suppose the characters would be engaged with more pressing matters, such as running out of air.
Given how many other recent movies have cost a lot more money, been given much more ballyhoo but have had much weaker plot, characterization and atmosphere, it seems a shame "Below" must rely entirely on word of mouth, or keyboard. I won't claim I was on the "edge of my seat" throughout but I definitely "bought into" the situation. There's a really lovely closing shot, like a shorter & underwater "Koyaanisqatsi," that no one should find overly corny or contrived.
Bottom line: if you can't find this one in a cinema or reach it before it goes away, keep an eye out for video. The studio made a mistake just blowing the movie off, it deserves better.
In one scene we see a seaman with pet fish in a tank, a nice ironic touch.
