One of the biggest announcements by Sony at this year’s E3 was not for the PS3, but for the PSP. The company said during its press briefing on Tuesday that it is developing a third-person shooter based on the Resistance universe exclusively for the PSP, called Resistance: Retribution. Here is everything we know so far about this blockbuster announcement.

Resistance Retribution is in development at Sony Bend, the same studio responsible for the Syphon Filter games on the PSP. Sony Bend has developed a highly-refined graphics engine which will be used in the new game, allowing for highly detailed environments and lighting effects, similar to what we saw in last year’s Logan’s Shadow. Retribution will reportedly be ready for release by Spring 2009, so the company has lots of time to improve graphics and gameplay before the game ships.

The storyline in Retribution will take place in Europe during the period of time between Resistance: Fall of Man and Resistance 2. Players assume the role of a former British marine who joins the resistance to fight the Chimera in Europe, after they develop a new method of converting humans to aliens:

"Set in the weeks after Resistance: Fall of Man, Retribution follows the story of former British Marine James Grayson. After a personal tragedy – he is forced to kill his own brother inside a Chimeran conversion center – Grayson goes on a vendetta to destroy every conversion center he can find. Eventually Grayson learns that his efforts have been futile ... in Western Europe the Chimera have evolved a new method of converting humans to aliens. The European resistance – the Maquis – enlist Grayson’s help, and he joins Cartwright and Parker in Operation Overstrike. The war to retake the European continent has begun."

The PSP game will include new enemies, new weapons, and new gameplay mechanics. A couple of new weapons will reportedly blend alien and human technology. There are the BM001 Razor and the Longbow 1S-1K sniper rifle. Sony Bend have spent a lot of time already trying to perfect the aiming system. The PSP game will rely heavily on auto-aim, but will also allow players to assume a zoomed-in unassisted aiming position for those hard-to-hit enemies.

One of the biggest selling features of the console titles has been the series’ strong multiplayer modes. Things will be no different on the PSP, with a variety of innovative ways to kill your friends on offer. All of the multiplayer modes, which include regular death match and a new mode called “containment” will be playable locally and online using infrastructure. Online support will be for up to eight players, which is somewhat disappointing but could change in the coming months.

So far, this game looks to be a sure-fire success on the PSP. The handheld has shown itself more than capable with other action shooters, particularly when using the third person perspective. Sony Bend produced two top-quality Syphon Filter games, and really took the time to tailor the control scheme and gameplay to the PSP. It looks as though Resistance: Retribution is in good hands, and we can’t wait to play the game for ourselves.