Single-player DLC can be a tricky thing. In Bioshock 2's case, the story had a clear beginning and ending. Rather than just splicing (ha!) a new level in the middle of the campaign or making stand-alone challenge levels (like the recent Protector Trials), 2K has this time opted for a self-contained bit of narrative set in areas of Rapture that we haven't seen yet in the previous games. For 800 Microsoft points ($10), you get a good chunk of content that will easily last you 5-6 hours and delivers a fantastic story that stands entirely on its own.
 
Saying too much about the story would risk spoiling it, but suffice it to say that you're a Big Daddy on a quest to leave Rapture with the help of a scientist. The plot revolves around a big supercomputer at the center of Rapture, The Thinker, which is apparently in control of all the day-to-day functions of Rapture. This being a Bioshock story, of course not everything is as it seems, but the climax is fantastically well done and honestly, I felt it was as great a narrative as either Bioshock 1 or 2 delivered, albeit on a smaller scale. I could even argue that the shorter length means the story is a lot more focussed and there is less filler. Given that the history of Rapture and the context in which the story unfolds is already known to the player from the main Bioshock games, the DLC focuses purely on its own strain of narrative and does so to great effect. If you think Rapture is played out or that there are no more interesting stories to tell within it, Minerva's Den will convince you otherwise if you give it half a chance.
 
Having not played Bioshock 2 for about half a year, I had forgotten that it's actually really fun to play. Minerva's Den takes on roughly the same formula of progression of its big brother, but shrinks it down to accomodate the length of this DLC. What that means is that you'll have access to the majority of the Plasmids and Tonics in the Gatherer's Garden right off the bat, but you'll have to pick and choose your skills because there isn't enough Adam to go and buy it all. Weapons and upgrades are found in the world, and before the end of the DLC you'll have all the guns of the main game plus a new laser cannon, and a cool new plasmid that creates a black hole to knock splicers around.
 
There are definitely moments where you'll probably get a slight sense of déja-vu, as the new areas don't feel radically different from what you've seen of Rapture in the past, but by the same token Rapture is as fun to explore as it always has been, and you will learn some interesting bits of Rapture's backstory in the form of its ubiquitous audio diaries. The strong visual style of Bioshock still carries it very far indeed, even if you might think there is little reason to go back to Rapture. If you've found yourself enjoying the atmosphere of these games in the past, you'll probably be surprised just how much enjoyment there still is to glean from just being in Rapture, partly because it's still a wholly unique setting in videogames.
 
I was blown away by Minverva's Den. For DLC to deliver such a lengthy chunk of gameplay complete with a fulfilling, self-contained narrative was beyond what I was expecting. It encapsulates everything that is great about the series: interesting stories, a beautiful and unique setting and an addicting gameplay formula. If this is the last time we return to Rapture, then it's a wonderful goodbye letter.