Since it looks like the PV has already been translated, here’s a detailed summary from the official site.

The world is extending its hand towards a forbidden peace (System). 2116 - four years since Tsunemori Akane was assigned to the MWPSB.

The Japanese government has finally begun exporting the Sibyl System and drones to the world. Chairman Han of the SEAUn (Southeast Asia Union), a region long affected by civil wars, implements the Sibyl System in the capital city of Shambala Float. Despite bullets flying everywhere in this zone, the floating capital manages to obtain momentary peace. The Sibyl experiment seemed to be going well.

At that time, a group of armed illegal immigrants enters Japan. They have full knowledge of Japan’s security system and manage to conduct acts of terrorism while evading Sibyl’s observation. An unprecedented number of illegal immigrations takes place since the enforcement of the Sibyl System and the ones to face them are the members of Division One led by Tsunemori Akane. Before long, the person who guided the terrorists appears.

That man used to be a Division One Enforcer and a former colleague of Akane’s.

Akane heads towards a solitary investigation in Shambala Float, in order to find out the true motives of the man she believed in and to ascertain the justice he himself believes in.

(Source: psycho-pass.com)