If you're interested in this series, I would highly recommend that you play the Mass Effect games in order. There are several reasons for this. Firstly, you can import your saved game from Mass Effect into Mass Effect 2 and then from Mass Effect 2 into Mass Effect 3. Secondly, Mass Effect is where you first learn about all of the species inhabiting the galaxy and their relationships with each other. Thirdly, the first one establishes and builds the character you will play throughout three games and lays the foundation of the story that will not end till Mass Effect 3. Lastly, if you play the others first, you will likely be disappointed with the graphics and gameplay mechanics of the original Mass Effect should you decide to play this one later. Let's say it would be like reading a book backwards.
The Mass Effect story is so involved and the characters so many that it's only possible to give the briefest outline here. The year is 2183 and the galaxy is populated by many species of which humans are one. The Mass Effect relay enables interstellar travel between solar systems and is an advanced technology left behind by a now extinct race called the Protheans. The Citadel, a city also believed to have been built by the Protheans, now acts as the diplomatic centre of the galaxy and is governed by a council of representatives from various races. It is very difficult to obtain a position on the council and so far no humans have occupied a seat. The council also employs special ops agents known as Spectres to handle situations where diplomacy has failed.
There is much interest in the extinct Protheans and the story begins with the discovery of a rare Prothean beacon located on the planet of Eden Prime. The council sends a contingent from the human military, Alliance, to investigate, which in turn assigns a team led by John Shepard to retrieve it. However, just prior to their ship landing, Eden Prime is attacked by a formidable AI species known as the Geth and its colonists murdered. After Shepard clears the area and finds the beacon, he accidentally comes into contact with it and receives odd visions that are hard to decipher. He also discovers that the Geth are being led by a council Spectre named Saren who appears to have gone rogue.
Due to Shepard's contact with the beacon and his insistence that Saren needs to be investigated, he is given command of a unique ship called the Normandy and sent to find out what the Spectre is up to. Along the way, he finds evidence of a mythical species known as the Reapers who are far older in origin than the Protheans. Shepard believes the Reapers are an imminent danger to the galaxy and that Saren's activities are connected to them. However, the council remains unconvinced that the Reapers exist at all. Gathering a special team of human and alien allies, Shepard sets out to various locations in the galaxy to trace Saren's movements and gather intel on what he is doing and what connection this may have to the Reapers.
This is the main story line, but there are also many side quests to perform throughout Shepard's travels. Mass Effect is mostly a role-playing game that usually includes some combat during the missions. A great amount of your time will be spent in conducting dialogues, finding equipment upgrades and deciding on the deployment of these to you and your team. Side missions are added to the game through speaking to various people and involve accomplishing certain goals as well as collecting a variety of things. There are also quite a few missions where you will use an armed shuttle vehicle called the mako to destroy Geth outposts located across the galaxy.
You can create a unique profile for Shepard by choosing from different backgrounds and classes, which will determine your particular talents. You are also given different dialogue options that determine whether you will gain points as a renegade or paragon, which in turn opens up further dialogue options. Each mission also requires you to choose two team members to accompany you. They also have various strengths and weakness and their particular talents can be upgraded using auto upgrade or you can choose to manage this yourself. Upgrades are achieved by gaining experience points in a number of ways including these side missions.
Some of the extra missions can become rather a bore and can be skipped if you want, but you will also be missing upgrades, credits and experience points by doing so. One problem concerns the length of time it takes the mako vehicle to regenerate its shields. You may just have to sit there and wait it out while twiddling your thumbs. It's a part of the game that is really overdone and very repetitive as there are quite a few of these. Some of the dialogue in the game can also drag on forever. All and all, it's not very exciting at times and more of a chore. However, the story is what really carries this game and it's top-notch.
Combat is really nothing great either. Once you obtain suitable upgrades and talents, it's like a warm knife through butter. What is good is the character models of the various species. They're plentiful and well rendered and their cultures described in phenomenal detail. You could spend hours just reading the historical and background information on each. One can appreciate the amount of work that must have gone into this.
Even though Mass Effect cannot be said to be the most exciting game in terms of action, I still feel it's an important segment to the series and shouldn't be skipped. It's often found cheap enough to get it just for the story if nothing else. Mass Effect 2 shows an improvement on the action end of things while maintaining it's role-playing elements and strong story line. Mass Effect 3 is a game that many people looked forward to as the conclusion in an outstanding saga. However, it ended in one of the greatest controversies in gaming history.