Like radio, film, and theater companies going back hundreds of years, BioWare games often have a very familiar voice cast from one production to the next. A Dragon Age II player can't help but hear Varric's dry tones from the Male Trooper in Star Wars: The Old Republic, nor can a Mass Effect fan miss hearing Commander Shepard herself in, well, almost everything.

The voice cast of Mass Effect 3 is enormous, and ranges from the famous — like Seth Green, Martin Sheen, and Freddie Prinze Jr — to the utterly unknown. BioWare regulars pop up everywhere, alongside newer actors. Because of the branching nature of the story, which depends so much in part on the widely variable events of the first two games, it's literally impossible to see or hear everyone in a single playthrough. To go through every fan favorite and well-known guest star would be a million-word essay, but here's a look at a dozen of these hard-working behind-the-scenes folks, from the lead character to a few surprising, fun cameos.

UPDATE: We've corrected the image of Kimberly Brooks (Ashley Williams), which initially featured the wrong actress. Also, due to popular demand, we've added a few more comparisons and profiles to the gallery. Enjoy!