It's made by Wizards of the Coast, the company that owns Dungeons and Dragons, where the game is set. Anywhere from 2 to 5 people play, representing different factions vying for power and control over the city of Waterdeep. Your goal is to collect victory points, which you primarily get by sending adventurers on quests in the city. You get those quests (and the adventurers to send on them) by assigning your agents to various buildings throughout the city. You can send them to the Field of Triumph to gather Fighters, or maybe Aurora's Realms Shop to earn money, or even to Builder's Hall to buy a new and powerful building to add to the city.
Or you can do my brother-in-law's favorite thing to do in the world and send your agent to Waterdeep Harbor, where you can play an Intrigue card. As you might imagine, an Intrigue card usually involves some sort of special or interesting action outside of directly gathering resources. At least when we play, though, most of those cards seem to be played to take away my adventurers, put a new obstacle in my way, or otherwise hinder me as we play. Of course, by doing this, he's sacrificing his own resource-gathering, since the agent he used to play the Intrigue card could have instead been used to earn him something he needs. But sometimes, delaying your opponent for a turn or two can be all you need.
Lots of ways to help people. Sometimes heal patients; sometimes execute dangerous people. Either way helps. - Mordin Solus
What I do love about the game is the number of different tracks and tactics you can take. Maybe you want to keep knocking out a lot of smaller quests (for each faction, there are two types of quests for which they'll receive a bonus at the end of the game) to grind out your points. Maybe you want to grab a few of the bigger quests with the heavy payoffs. Or purchase and build a number of buildings that you know your opponent will need (every time he uses a building you paid for, you get victory points, money, or adventurers of your own). Of course, you're always at the mercy of a well-timed Intrigue card.
After having played it a few times, there is one thing I want to do: play it with more people. Not just play it again (though I do want to do that), but with more opponents. So far, all of my games have been one-on-one, and I can only imagine the new drama that will open up when there are more people involved in the game. I'm also intrigued at how the mechanics will start to change--as you add players, you get fewer agents to play each round, which means each action counts more. However, given that there are limited resources to gather (remember I mentioned getting Fighters from the Field of Triumph? Well, another player needs those Fighters for their quests, and only one agent can hit up the Field of Triumph each round, so you're out of luck), it seems like having more people would cause the players to diversify their strategy as well. If nothing else, it seems like it would be easier to hide in the shadows, gathering all your resources until the last round when you can suddenly play a stack of quests that you've been hoarding.
The game itself is beautiful--it's really well-made, from the tokens to the little wooden agent pieces to the map and the cards (all printed on high-quality stock). All the pieces actually fit into the box (though you'll want to check out the diagram the first time). The board is a good size--you shouldn't have difficulty setting it up on the dining room table.
Would recommend it for anyone looking for something a little more interesting for their next game night--the only advice I'd give is to try and have someone who has already played it there to explain it to the group. Better yet, do a "trial run" of the first round of the game so everyone gets an idea of how it's played before clearing everything away and starting fresh. Also, if you're up for it, the good folks over at Table Top have put up one of their games (though edited down--you only see a few rounds of the game):