From the storytelling, to the character interaction, to the visuals, this is one of Bioware's finest, and a must-own.
Their answer is Mass Effect; a game that takes and improves upon their successful formula for storytelling, and gives new definition to the term 'cinematic'. Mass Effect begins in the future. The Earth, it turns out, is one of many planets in the galaxy inhabitied by life. An ancient artifact, found on a planet in our solar system has enabled us to make contact with other species'. Humans become one of the newer members of an intergalactic council, which encompasses representatives from many of the galaxies' species. Depending on your choices during the deep character creation process, you can come from a variety of backgrounds which effect how the characters in the game view, and treat your version of Commander Sheperd. This is a fascinating way to begin your journey because it gives you a feeling of what your character has been through, up until the point where the game starts. The first thing you notice about Mass Effect are the detailed, streamlined graphics. When you enter the deck of your commanding ship, consoles in your peripheral bustle with activity. Crew members work intently. Adding greatly to the immersion is the audio. Everything from the sound of crew members pressing console buttons, the the pulse or your ships engine sounds just as it should, without being intrusive. The music is simultaneously subtle, and dramatic, coming to the forefront at pivotal, dramatic moments in gameplay. The choice of your characters response to almost every piece of spoken dialogue is astounding. You are given summaries of responses your character would give. You never quite know what is going to be said, but the summary gives you a good gist of the direction of the comment. Through trial and error, you begin to realise that the bottom-half reponses in the dialogue tree and generally abrasive, and to the point, whereas the top half are more subtle, long-winded responses. This means you basically choose your characters personality, temperament, and attitude. So rather than being a passive observer to a story being told, you are a substantial part of it, constantly changing the course of your journey through you choices.
The voice acting deserves special attention. Never before has a game been so flushed out with a cast of complex, believable characters. From alien merchants, to your squadmates, to the game's main villian, all sound, act, and react uniquely enough to make you forget you are playing a videogame.
You may think to yourself while playing that the characters and universe would be highly regarded in television or film, and you would likely be correct. An astonishing amount of creativity went into thoroughly flushing out the game's universe. To make it feel substantial, unique, and lived in.
You encounter unique personalities, how you deal with them, treat them, or even if you let them live is all up to you.
The combat in Mass Effect has taken criticism. Mostly due to the complexity of the operations, and the lack of instruction given to fully understand the combat/magic mechanics, which could take the average player 6 or more hours of playtime to fully grasp. But the game doesn't shove it down your throat. You learn slowly, through a progression of various encounters, each a bit more challenging than the last, and forcing you to adapt and learn more. Would it have been more efficient to explain the systems in a combat tutorial? Perhaps, but instead the player is left to explore it's complexities, which I found enjoyable. You almost always fight with a squad. 2 other characters which you get to choose before each mission. Their strengths are listed plainly for you to see, so it's up to you whether you want a group that is combat intensive, tech capable (hacking CPU terminals, disabling and overloading mechanical enemies), or biotic (the game's mysterious magic) specialized, or a combination of any of them. Another complaint is the framerate, which I found to be little more than a minimal distraction at times, the screen never chugged too much, and if it did, it corrected itself within a few seconds.
Mass Effect is fairly linear. Not overwhelmingly so, but you are usually nudged in a certain direction, even once you've gained the capability to go almost anywhere in the galaxy. The optional side-quests are a mixed bag. Some are tedious, and overly long. Some are short, and pointless. Some are fun, with small rewards. When you decide to get on with the main game, however, you're always given the option to go back to any them, should you change your mind or get bored.
What this all boils down is scope. Never before has a RPG attempted to reach for the stars quite like this. And it mostly succeeds. From the phenomenal story, the believable universe, the beautiful, high resolution worlds to the too-good-to-be-true finale, this is one of gaming's biggest RPG treasures. Don't miss it.