Mass Effect 2 is new Bioware RPG game that has been evolving as Knights of Old Republic introduced us to Bioware's unique mix of story, moral options, RPG elements and action. It also takes idea positively towards shooters, slimming down RPG elements significantly. Still main part of idea is maintained game with moral options that enthusiastically change outcome of story.

Mass Effect 2 is sequel with story building on events of first game. On patrol to hunt down any residual geth, Normandy ends running into something alien, far more than it could chew. Cue explosions, epic space battle video clips have Normandy getting shot to bits by strange vessel. Normandy ends as wreck and as most of crew manages to escape in time, Commander Shepard, failing to reach escape pod in time, ends up lost and presumed killed.

Main character killed 15 minutes into game generally confused story. Mass Effect 2 solves this by forwarding many years and find out that stories of death of Commander Shepard were untimely. A secret "Lazarus Project" by Cerberus, shadowy pro-human organization, controls to rebuild and renew hero from what of body was improved at Normandy crash site. Turns out Cerberus have work and for that they require Shepard. Illusive Man, strange lead figure of organization fills in blanks and presents his case humanity requires Shepard as threat even more unsafe than geth is threatening. Human colonies are attacked; population seized by unidentified enemy and nobody is taking threat sincerely.