Somewhere inside this bloated, unpleasant movie is a genuinely interesting science fiction tale struggling to get free - it fails. To watch it is to watch potential die under pressure from mandate: A nifty-sounding idea (an extraterrestrial Noah's Ark retelling in which humanity tries to talk an alien god-figure out of his doom-flood decision) dies painfully from contorting itself into a LOUSY idea (an ID4-ized rehash of the same-named 1950s scifi classic.)
In case it's been awhile (or never) on your end, the original film details the arrival of alien ambassador Klaatu and his robot bodyguard Gort, come to inform humanity that we've got another thing coming if we think the rest of the galaxy will ALLOW us to develop space travel before we get our pesky Cold Warrin' ways under control.
This time around, environmental destruction has, of course, supplanted the Cold War and Klaatu (Keanu Reeves) isn't at all in a diplomatic mood. As it turns out, The Aliens have decided that our planet-destroying ways pose too much danger to all the OTHER species on Earth, so we're too be wiped out while he spares samples of the others. This is where the new Gort comes in - he starts out looking like the original, then winds up as something completely different.
Oddly enough, it's the callbacks to the original film that drag it down - the "new" elements are almost uniformly interesting and provocative. The new Gort looks cool, but the effects used to realize him are awful and it makes no sense for him to spend two acts of his existance looking like a forty-foot version of the original. The film takes a long detour wherein an elderly scientist (John Cleese) tells Klaatu's human pals stuff we've already figured out just so they can do the "blackboard bit" from the first one.
The director is Scott Derrickson, who made the similarly-squandered "Exorcism of Emily Rose" a few years back. Interestingly, this now means he's been responsible for making preachy, poorly-made genre films for both the Right AND the Left - way to branch out.