The game is a pure masterpiece. You feel like you're part of a live show where every line and every word you pronounce can change the outcome. You're the same old Shepard (saved by Cerberus) and asked to save once more the humanity from the Reapers. This time the reapers work with the collectors.
As gameplay, it's a third person RPG shooter and you have to possess certain "riches" and credits in order to progress and upgrade you weaponry. You have a little trace of strategy in the gameplay and you can ask you team mates to go in certain places.
Your team members have special abilities which can be upgraded in time, as well as Shepard's.
The races you meet through the galaxies are well drawn, each of them with its peculiarities, and Shepard can convince them to work together or fight them.
Overall a real pleasure to play this game.