Xbox 360 owners who completed Grand Theft Auto IV's "Museum Piece" mission were rewarded with an Achievement with the cryptic name "Impossible Trinity." It was easy to just shrug off the whole thing and continue forward in the game, but some clever gamers figured out that the Achievement title was a direct reference to the two-part cycle of downloadable episodes Rockstar had promised to 360 owners. "Museum Piece" brings together three characters whose paths closely intertwine, but rarely cross. By now, most gamers should have thoroughly explored the first side of the Trinity; Niko's story. The Lost and Damned and The Ballad of Gay Tony explore the other two sides of the Trinity. Of course, not everyone is subscribed to Xbox Live; these people could have missed out. Thankfully, Rockstar released a disc containing both of the episodes. Grand Theft Auto: Episodes From Liberty City is a fantastic companion to one of 2008's best games; it's modestly-priced and packed with content.

The Rage engine isn't raging as much as it is aging. However, Liberty City is as lively as it ever has been, and the potential for unscripted chaos is ever-present. Each episode features a similar presentation, but it's amazing how far a swapped-out font can go towards establishing the theme. The Menus in The Lost and Damned look like they should be embroidered on the back of a leather jacket, while The Ballad of Gay Tony's is, well, rainbow-colored. The in-game cutscenes never go beyond what you see in gameplay, but the animations are lifelike and the attention to detail is very impressive. I did run into a mild bug that crippled the framerate enough to force a reset. I can't properly identify the problem without exposing myself for what I am -- a gamer who is completely ignorant when it comes to programming issues. Anyway, this happened only once, and under very bizarre circumstances. By "bizarre circumstances," I mean a yacht managed to ramp off a pier and into the highway, and the two enemy helicopers chasing me were suddenly left unmanned. I was wondering if the Rapture had hit Liberty City.

Exceptional sound design is something of a trademark for Rockstar's games, and Episodes From Liberty City adheres to that proud tradition. The excellent licensed soundtrack, superb writing, and outstanding voicework create an unrivaled sense of immersion. It's good in The Lost and Damned, but it's positively brilliant in The Ballad of Gay Tony. Mario D'Leon provides a good performance as Luis Lopez, but D.B. Cooper and Omid Djalili absolutely steal the show. Never before (and never this much) have I grown to love two characters as utterly wretched as Gay Tony and Yusuf Amir. The voice acting is that good.

Do not play Grand Theft Auto: Episodes From Liberty City if you have not finished Grand Theft Auto IV. If you do, you won't be able to appreciate all the nods to gamers who saw Niko's journey to the end. You'll still love it all, but too much will be lost on you. These episodes are meant to be experienced as sidestories: they aren't nearly as long as GTA IV, even when you compact both of them into a collective whole. Be sure to take that into account before making a decision.

The Lost and Damned follows a rough chapter (no pun intended) of the Lost Motorcycle Club. It begins as the Lost's President, Billy Grey, is released from court-ordered rehab. You are Johnny Klebitz: the Vice President of the club, as well as Billy's right-hand man. After Billy's release, it quickly becomes apparent to Johnny that the MC's acting president intends to carry out a seriously unwise agenda. It's a dark story that manages to retain the franchise's trademark sense of humor, but the cast of characters aren't easy to relate to -- or like, for that matter.

The Ballad of Gay Tony differs from The Lost and Damned in that it's far more gonzo than it is gritty. You play as Luis Lopez, business associate and bodyguard to nightclub booster Anthony Prince. From his drug addiction to his admitted affinity for horrible people, Gay Tony is a neurotic train wreck... and he knows it. As Luis, your job is to get Tony out of every hole he digs himself into. You'll come into contact with several new and familiar characters, the most memorable of which is Yusuf Amir, the real estate magnate from Dubai whose plans for Liberty City pave the way for some truly outrageous moments.

Structurally and gameplay-wise, Episodes From Liberty City is identical to Grand Theft Auto IV, save for the new mechanics introduced in each episode. Each episode follows the errand-boy-in-an-open-world template, but they both offer their own little twists on the formula.

Episodes From Liberty City could very well have released The Lost and Damned and The Ballad of Gay Tony and called it a day. However, they decided to add some fantastic new multiplayer modes to an already-robust online component.

The Lost and Damned's best modes are Witness Protection and Lone Wolf Biker. Witness Protection takes a page from one of the episode's most memorable missions and places you in charge of defending (or destroying) a bus full of participants in the LCPD's witness protection program. Lone Wolf Biker is essentially Burnout Paradise's Marked Man challenge with a GTA flavor.

The Ballad of Gay Tony doesn't add quite as much multiplayer mayhem as its brother episode, but it offers vastly updated versions of the original game's multiplayer modes. I had the most fun with the updated Free Mode; it contains new weapons, vehicles, and most importantly, the ability to BASE jump from several locations.

Episodes From Liberty City doesn't offer quite as potent a challenge as Grand Theft Auto IV does. The final mission of The Lost and Damned is probably the most difficult sequence in this collection, but you'll probably get through it in a few tries. The side missions aren't that tough, either. From dealing with The Lost's war against the Angels of Death to helping Luis Lopez's intellectually-stunted childhood buddies in the drug trade: all of this pales in comparison to the brutality of GTA IV's bank heist mission. This is to the game's credit.

The introduction of mid-mission checkpoints goes far in whittling down the game's difficulty. This is a really great tweak; Grand Theft Auto IV often forced you to make each car trip a number of times, until you got to the point where you memorized the dialogue -- it was extremely frustrating at times. The difference here is clear and convenient.

The Ballad of Gay Tony has a grading system that strongly boosts the episode's replayability. Different challenges must be met in order for you to obtain a 100% rating. These challenges don't make themselves known until you've completed the mission in question, and you can't return to different missions until you've completed the game. The challenges are well-designed and often funny, but they are difficult to meet. Still, the online leaderboards make it even more appealing.

The two episodes in Grand Theft Auto: Episodes From Liberty City are each set against a different backdrop. Therefore, it's fitting that the game introduces some new mechanics that let you sink even further into the experience.

The Lost and Damned really makes you feel like part of a twisted brotherhood. Riding in formation with the Lost MC makes you feel like a badass, and participating in races will make Road Rash veterans smile. If you ever need assistance, from guns to bikes, give Terry or Clay a call. The whole premise is unsavory on paper, but in this game, it feels just right.

The Ballad of Gay Tony doesn't make you a member of a biker gang, but you will do some seriously crazy stuff, nonetheless. Your partnership with Yusuf Amir will see you through a number of missions that almost feel like Rockstar's answer to Volition's Saints Row 2 (which Starscream referred to as "the Michael Bay version of GTA 4"). You can BASE jump from numerous high spots to painted targets or moving vehicles. If you spent hours at a time in San Andreas dropping Carl Johnson from a Hydra, opening his parachute, and cutting said life-saver only to hear what he would say in freefall, you are going to love this addition -- especially in multiplayer. You can also participate in Drug Wars, which is really nothing more than violently ripping off buyers and sellers, considering your partners in crime. If you want to put in some hours at Maisonette 9 or Hercules, you can get down on the dance floor; if you don't, expect Dessie to call you often. Oh, and you can participate in cage fights.

Grand Theft Auto: Episodes From Liberty City rounds out the Grand Theft Auto IV package quite nicely. It offers most everything you'd want to find in a GTA game, from intriguing characters to biting satire; from well-polished single player missions to fantastic multiplayer design. It would appear that it is time to close the book on Grand Theft Auto IV, but Episodes From Liberty City is a remarkably satisfying sendoff that will leave fans in anticipation on where the series will go next. Well done, Rockstar. Here's to the future!