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This article is about the infamous prison ship, Purgatory. Any resemblance to any other ship, in Mass Effect 2 (Bioware, 2010) or otherwise, may or may not be purely coincidental. This ship is featured in the story of the same name, Purgatory, by Elliot Frost.
The Purgatory is a frigate class vessel built by a large outer rim slaver group called Sons of Blue, who has since been destroyed by Alliance Security. The ship and its crew escaped the destruction and cut all ties to the Sons, becoming a privately owned prisoner transport ship. The ship and its crew have since traveled the galaxy, taking the most dangerous and volatile lawbreakers of the universe out of the hands of local planetary governments, for a fee.