It was one hell of a gamble, entrusting a mega-budget epic with the biggest movie star in the world to a director who had gone from being considered the next big thing to a massive punchline, an auteur who thought he could be like Stephen King and make anything scary (The Raft, anyone?) - including Mark Wahlberg talking to potted plants. Hell, the best thing M. Night Shyamalan has done in a decade is inadvertently give Andy Samberg the idea for a great impersonation.
Maybe he and Will Smith just bonded over their love of the city of Philadelphia. Maybe Smith was a control freak for all the right reasons. Regardless, After Earth is a beautiful bit of world-building that - if you're not chronically opposed to Will Smith and his kid - will transport you to the kind of adventure that I know I imagined in the backyard when I was younger than Jaden Smith.
Though this level of epic is new for Shyamalan - at least in any competent way, thank you Last Airbender - many of his old signatures abound: lots of quiet, lots of stillness, a lead character who's a kid that sees dead people (in his dreams). There is no sudden surprise ending, but there are several moments which he chooses to play like a horror movie - the principal villain-slash-metaphors in this future are the Ursa (wait...is THIS why Man of Steel went with "Faora" instead?): ugly, loud alien monsters who can smell your fear, and thus become relatively harmless foes only if you can manage to be totally unafraid of them, a condition called "ghosting."
The world of After Earth is elaborately conceived, to a greater extent than is shown onscreen: Peter David and other writers collaborated on a history of the future from now until the thousand years hence point, but you don't get much of that detail here - it's been saved for comic books and tie-in novels. What we do know is that humanity ruined our own world, and fled to planet Nova Prime, where people live like space-hippies in eco-sound dwellings, while still being militarized as all hell thanks to those pesky Ursa. It's a bipartisan future, and people have odd accents which come and go.
Will Smith bears the unfortunate name of Cypher Raige, and even pronouncing the surname "Raishe" half the time doesn't change that. Having lost a daughter to the Ursa, he's tougher on son Kitai (Jaden Smith), and decides to take him on a space trip to get his head straight. But there be asteroids, and there be crashes...and when the spaceship makes a forced landing, it's on future Earth, where, in a mere thousand years, lions, baboons and eagles (oh my!) have mutated into hungrier and way more evil versions of what we had before. Also the spaceship was carrying an Ursa egg, and it kinda-sorta hatched, because nobody could possibly see that one coming.
Most of the crew dies, Cypher breaks both his legs, and only Kitai, who was noticeably the only passenger to wear his seatbelt, comes out unscathed. But the emergency beacon is in the other part of the ship 100 km away. And Kitai failed Ranger training - with nothing but his critically injured father's voice in his ear, can he go it alone on a planet where even the air has turned hostile to human life? Well, there'd be no movie if he didn't have a chance.