Mass Effect 2 opens up after the events of the first Mass Effect, with Commander Shepard in a pretty bad situation. A new enemy has appeared in the galaxy and is presenting a threat to humankind on par with the Reaper that Shepard defeated in the first game. Things have gotten so bad that Shepard was thought to have died in combat. Fortunately, he was rescued and recruited by a shadowy underground group who is looking for his help on a suicide mission. Shepard is the only human capable of pulling off this mission successfully, but he can't do it alone. Instead, he'll have to recruit the absolute best the galaxy has to offer to aid him in his quest, à la "Ocean's 11."

All of this sounds like a pretty interesting story, but what really makes it stand out is what Bioware has implied about the way the story plays out. In fiction, any seemingly impossible mission is dubbed as a "suicide mission," but in Shepard's case, it may actually be true. The way the mission plays out is going to be influenced by the assistants you recruit and how well you train and equip them. Success or failure isn't the only thing to be determined by this, though. We were told that it is possible that Shepard won't survive this mission, even if you're successful. The above isn't a spoiler for the game's ending, mind you, but a simple statement of fact. A player's actions are going to influence the outcome of the story, and that includes whether Shepard lives or dies. This doesn't just mean that Shepard might fall in combat, however; the actual ending may indeed involve Shepard dying in order to complete the mission, and that would be the end of that particular Shepard's story. A player who survives will be able to continue playing the game after the story is finished and bring the character over to Mass Effect 3. A Shepard who screws up will be nothing but an honored memory.

The character continuation seems like it will be a major feature of Mass Effect as a franchise. Bioware confirmed that players who have save data from the first Mass Effect will be able to transfer it over, with the data containing a record of every choice that particular Commander Shepard made, which will then alter the world of Mass Effect 2. There are no specifics yet on what exactly your choices will alter, but considering the fact that the choices made during the course of the game determined who lived and died, it's safe to assume that there will be certain plotlines that only exist for certain Shepards.

Our demo opened up with Shepard driving in a futuristic flying car toward a fancy skyscraper. He and his forces were searching for Thane, known as the universe's best assassin. Obviously, Thane would be a great addition to Shepard's team, but getting him to join up is going to require some effort. Even tracking him down takes a lot of effort, and Shepard decides grab the bull by the horns and intercept Thane at his next assassination target, an Asari businesswoman. This opening scene is a simple conversation scene, as is often seen in Mass Effect, but the cinematography is a lot tighter. It feels like a shot from a movie, with the city racing around behind the duo and the camera acting more dynamically instead of just showing two talking heads. Before long, they arrive at the skyscraper only to find that the Asari's guards are already out in force.

When Mass Effect was first introduced, one of the more interesting features they were planning was the ability to interrupt people during conversations. You could butt in with your response before they were finished, and this would change their interactions with the player depending on when and why they interrupted. Unfortunately, the system didn't work out, and the conversations in Mass Effect remained polite — at least as polite as one can when being a jerk is always a conversation choice.

However, this is not so in Mass Effect 2. Shepard has the ability to interrupt conversations, although not quite in the same way as you'd expect. Instead, as he's talking to someone, a button prompt may pop up. Our demo example involved Shepard questioning a guard in order to find the location of the aforementioned assassin. Shepard could try to politely get the information out of him, but that isn't going to be every player's option, especially once the guard starts getting belligerent. In this case, Shepard could interrupt the conversation before the actual trouble starts. "Interrupt" caused Shepard to brutally push the guard through a glass window to his death, followed by a parting quip. It's perhaps not the most diplomatic solution, but many gamers are going to be quite happy to hear that you can take action on an enemy before you finish a polite conversation with him or her.

After Shepard's violent outburst, we're treated to a view of the combat. The very basic gameplay looks very similar to the first title. It's still a third-person, over-the-shoulder shooter, and most of your same abilities have returned. You can still duck behind cover, switch weapons, call up your special ability menu and so forth, but a number of improvements and refinements have been made to the system to make it friendlier for players. For example, your allies can now be ordered to move to specific locations individually, which allows you to flank enemies with greater ease. Skills can be bound to shortcuts on the menu, allowing you to have full combat functionality without the constant need to stop, although pausing and selecting a move manually is still an option. There are also nine types of new weapons available, including special heavy weapons like rockets to send enemies flying. Generally, weapons are more accurate and more powerful, and your focus is going to be less on making weapons usable and more on improving the abilities of those weapons using your character's natural skills. The damage system has also been improved to allow for limb and head damage, so skilled players can focus their attacks on the enemy's weak points instead of simply spraying and praying.

Eventually, the team finds the Asari, and after an angry confrontation with Shepard, she is killed by Thane, who sneaks down from the room and quickly and brutally dispatches both his target and her guards with his bare hands. Thane is both a new type of alien and an example of the greater brutality that one will find in Mass Effect 2 over the previous game. While it certainly isn't tremendously bloody or violent, the entire tone of the game is darker. Considering that the last game wasn't exactly a cheerful or happy title, the shift is really noticeable. The world feels less like a growing multicultural society and more dank and grim, as is fitting with the danger that the universe is in and the people with whom Shepard is working. Indeed, Bioware promises that this is a game no one is particularly safe and a happy ending is not guaranteed.

Mass Effect 2 is shaping up to be a very interesting game indeed. The gameplay is a natural evolution of the concepts introduced in Mass Effect, and while nothing tremendously huge has changed, there are enough modifications and tweaks that it should be a far more enjoyable experience for newcomers and veterans alike. The story line is where the game looks to really shine, as Bioware seems to have figured out a good way to make players actually consider the costs of their actions by putting their persistent character in a real dangerous situation. It's a unique idea, and one that Bioware is well suited to pull off, and we'll be watching Mass Effect 2 with great interest to see if they succeed.