With Assassin's Creed: Revelations being the third Assassin's Creed release in as many years, a fear of trepidation that the series would be back with diminishing returns isn't unfounded. Look at what an annual release schedule did to the once-great Guitar Hero: it takes time for developers to create and implement new gameplay systems and features. I went into Revelations skeptical and expecting to be unimpressed—and being wrong never felt this good.

The first Assassin's Creed came out in 2007 and felt like a proof of concept. Regardless of how beautiful the Crusades-era Holy Land setting was, the game's mission structure and environments were monotonous and bland. It was the video game equivalent of a supermodel serving you plain oatmeal. But it had potential. In the two years between the release of Assassin's Creed and Assassin's Creed II, developer Ubisoft hammered out the template for sequels to come.

With AC II, all that remained from the previous excursion were the big-picture elements. Rote missions and boring combat got the axe while a large go-anywhere parkour-anything historical environment—this time, Renaissance-era Italy—and the ongoing war between an ancient order of assassins and the Knights Templar stayed. And this is where it gets a little tough to explain.

Backstory—or lack thereof

In the first game, you played as shamed assassin Altaïr ibn-La'Ahad. From AC II through Revelations you're playing mainly as Ezio Auditore, an Italian assassin. They tie together through Desmond Miles, a twenty-something bartender kidnapped by modern day Templars. Desmond is the descendant of Ezio and Altaïr, and the Templars access genetic memories stored in his DNA via a machine called the Animus. This technology has a dark side: the Animus is destroying his mind.

The fiction is dense, and Revelations assumes you've played the three games before it. There are no recaps at the the story's outset nor during the lengthy campaign. While the narrative of last year's Brotherhood was a grind, taking too long to get anywhere or do anything interesting, Revelations is much more focused and personal. Flashbacks to Altaïr's life break up Ezio's quest and bring a tale of redemption to the table.

When we first met Ezio in AC II he was 17. Now pushing 65, he's searching for the Masyaf Keys that unlock the library in the Altaïr's deserted Syrian base. Ezio is hoping that whatever is inside will bring him peace and give meaning to his life. His age comes across not only in his voice and awesome new beard, but in his movements; in Revelations, he's weary and battle-hardened. Before, Ezio struggled to put weight behind his blows—here he eviscerates enemies almost effortlessly.

This is a game with two heroes. As a character who spent the Crusades putting hits on Muslim and Christian leaders, Altair suffered because he was trapped in a bad game. It wasn't until his re-emergence in AC II that I took interest in him. It's sad, because, until this point, his role was underutilized in the series. While I was fully invested in Ezio's story, I couldn't wait to get back to controlling Altair at each scheduled interval. This is as much the fault of being slightly tired of running around as a randy Italian for the past few games as it was wanting to see how Altair's story connected with Ezio's.

New tools like the hookblade and grenades make for killer additions to enemy encounters. With the former, you can pull a guard's head down and then shoot him in the face with your wrist-mounted pistol. You can craft a stink-bomb out of skunk oil and other ingredients to stun a group of enemies so you can sneak by undetected. The hookblade also replaces the series' ill-named jump glove, making movement a much smoother affair both horizontally and vertically.

The third dimension

When I ascended my first roof in Constantinople and began running around, a sinking feeling started setting in: I was definitely playing another Assassin's Creed game, only this time the setting was a dusty brown and yellow. But as I progressed, the city's idiosyncrasies revealed themselves. What separates this setting from previous environments is its density of buildings and lack of verticality. The reason for very few tall structures is explained in the story, but from a gameplay perspective, this makes the treks to the tops of mosques and Templar towers all the more memorable, especially in 3D.

I've played a majority of the stereoscopic 3D games available and Revelations is the best I've seen. Usually playing a game in 3D results in sacrifices in visual fidelity, as fine details melt away and jagged edges appear on what should be straight lines. Not here. Climbing to the top the Galata Tower and looking down induced a sense of vertigo and brief nausea I haven't felt since climbing the Agency Tower in Crackdown. 3D makes finding your way up spires easier, as every brick and detail juts out of the background at you.

In my 20 hours with the campaign, I only took my 3D glasses off once, and that was to navigate a nearly pitch-black cavern. 3D glasses make everything a little darker, but to be fair, even in 2D I had to max out the game's brightness to see where I needed to go.

It’s possible to just run along roofs in a straight line with little getting in the way or breaking the flow of your movement. For me, the parkour always felt staccato in previous games; just as I would hit a groove, the game would stop me and I'd fumble over a ledge or hit a dead end. Locomotion here feels less abrupt, especially when scaling a vertical surface. The world is much more empowering.

This is important, as you are given control of a team that will kill for you. Curating your personal assassin hit-squad is better this time out, and earning their allegiance isn't always as simple as stopping guards from picking on themt. Sometimes I had to tail a pickpocket while others I freed from captivity. Your posse is more important to the narrative, as well. Using them is always a treat: you target an enemy and they pop out of nowhere and to kill them. When the target is dead, they disappear into the shadows. As in past games, you get to level up these side characters, giving you a sense of control and ownership.

Revelations' biggest achievement isn't what it introduces to the franchise, it's how well it polishes everything it carries forward, story included. The hours melted away while I was playing, and I kept wanting to go further to see where the story would take me next. I was still playing at 5 am this past weekend not because I was on a deadline, but because I didn't want to stop—I felt like a kid on Christmas Eve forcing myself to sleep. When the credits rolled, I had enough closure for the story so far, but was left with just as many new questions. On the plus side, I only have to wait a year for those answers.

Assassin's Creed: Revelations is out now on the PS3 and Xbox360. The PC version will be released on November 29.