RoboCop is in trouble. His old enemies, the OCP Corporation, are out to get him. So ... they kill a black cop and make him into a RoboCop clone, only his armour is painted black and instead of one pistol, he has two. Twice as good with twice the firepower, eh? To combat this terrible foe, RoboCop gets a sidekick who reminds me of Trinity from The Matrix, only with less wire-fu and a lightsaber instead of a gun. Oh, and halfway through the four-film series a heretofore unmentioned villain shows up like a deus ex machina and wants to infect the city's computer network with some nanotech that will destroy the world unless the heroes can stop him.
I really don't think I have to elaborate further than that on the story. It speaks for itself.
The special effects are predictably pathetic, far worse than even the live-action TV series of the '90s (from which this incarnation also steals footage; you can easily tell where, if any bit looks good it's because it's old series footage). Bullets pinging off armour create small CGI flares that would look good in an old videogame. The Special Forces troopers wear paintball gear. And it seems there is perpetual night in the future (except in the reused footage) because of the camera settings -- Everything is Dark and Scary. Or Depressed, more like.
Let's not mention the music. Gone is RoboCop's awesome main theme. Instead we get a Western-style jingle that is hilarious where it works best (not in a good way), but usually just repetitive.
I don't recommend these films to anyone, friend or foe. RoboCop fans will be outraged (as I was) at how the franchise is treated. Those with no investment in the character or his universe will just be bored to death, sigh, and give the box away to charity after watching the first hour-and-a-half.