This started out as me re-writting TDKR. I'm sure you can salvage a couple of nice scenes from it:
Open the movie with an attack on Wayne Manor; it is completely leveled. Alfred is missing in action. Bruce Wayne is presumed dead. A corpse found in the ruins is identified as being Bruce Wayne.
On the other side of the world we find Bruce in a monastery belonging to the League of Shadows. It is built on the wreckage of one hed previously destroyed. Here Bruce is introduced to Talia al Ghul. During their meeting we flashback to the events leading up to the attack on Wayne Manor.
Flashback: Talias Story: Talia al Ghul and her people follow Selina Kyle to Wayne Manor. We see Selina attempting to steal something from within the manor, shes interrupted by Bruce. She drops her warning about a coming storm. Then all hell breaks loose Talia and her squad attack. Selina escapes through trickery and speaks to someone via communications device. Elsewhere on the grounds, Firefly finishes planting his explosives and sets them off. Selina escapes in the chaos; Talia abducts Bruce.
In Gotham, Alfred refuses to belief that Bruce is dead. He finds a bit of iconography in the rubble and thinks he recognizes it. Accessing the bat caves computer, Alfred discovers that it belongs to the League of Shadows, specifically a splinter group that his men encountered in the past. It terrifies Alfred. He brings his findings to Comissioner Gordon.
Alfreds journey to the GPD gives us a look at a post Dent Act Gotham. While much of it seems fine, graffiti indicates a growing resentment toward the semi-police state imposed by the Dent Act. Within the GPD, we learn that crimes within the Narrows and other lower income areas are skyrocketing. People thinking they have nothing left to lose are getting more aggressive. Gordon seizes on the opportunity to rally Gotham against the terrorist threat presented by this League of Shadows splinter group.
In the League of Shadows Monastery, Talia tells Bruce that shes come to him for help: she needs him to help her put away Bane and his band of followers, his Suicide Squad.
Cut to, Banes sewer lair: we see Deacon Blackfire preaching to masses of the disenfranchised, against the greed of Gothams elite and the corruption that made the Dent Act a reality. Catwoman is off to the side, wondering if the Deacon has actually read the legislation; she has and thinks his message is ********. Deadshot is having reservations about carrying out a hit on Gothams mayor he likes the idea of the Dent Act because it wouldve put away people like the pedophile that killed his boy. Bane reminds Deadshot that its people in the upper class, like his mother (who had hired the thugs, including the pedo), that backed the Dent Act. This gives Deadshot the resolve to carry out his hit. Firefly reports in that the charges have been set as Bane requested.
Cut to League of Shadows Monastery: Talia recounts Banes origins to Bruce a wandering mercenary that was imprisoned by a warlord, and later trained with the League of Shadows. Bane was excommunicated when he gathered a following from the Leagues ranks and carried out a renegade mission the assassination of the warlord that had imprisoned him; in response, Bane was excommunicated. Talia believes that Bane sees Bruce as someone unappreciative of what hed been given by Ras al Ghul.