This movie will inevitably be compared to Ong-Bak, and deservedly so. This movie has the same extreme high energy, but it has a *little* more story. It's kind of a cross between Ong-Bak and Escape From New York. It's set five years in the future, in the Paris ghettos. The government has put up a huge wall around District 13, a particularly problematic section of town due to gang violence and drugs, and the gate is guarded by police 24 hours a day. The philosophy being, I suppose, just to lock the deviants up together and hope they just kill each other off. And to hell with the innocent people who just happen to also live there.
The police discover that a neutron bomb has been put somewhere in that district and set to go off in 24 hours, so they pair up a cop who is capable of deactiviting it and an ex-thug who knows the streets of that district. There's a bit of a twist, which is kind of interesting. But the real juice of the movie comes from the action. A great, fun, machismo kind of movie - ain't nothin' wrong with that. :)