Activision ATVI has unleashed what is expected to be the biggest game of the year with Call of Duty: Advanced Warfare. This year, the publisher offered a Day Zero Edition of the game to give its most rabid fans a 24-hour jump on the less hardcore gamers. Retail events around the world counted down the launch like it was New Year’s Eve.

Michael Pachter, video game analyst at Wedbush Securities, thinks Activision will sell 21 million copies of the new Call of Duty this year, and an additional 2 to 3 million copies in 2015. That would equate to $1.26 billion in sales this year for the game, which has topped $1 billion in sales each of the last five years. After being outsold by Take-Two Interactive’s TTWO Grand Theft Auto V last year, which stole the “biggest entertainment launch of the year” bragging rights, Activision and new COD developer Sledgehammer Games are poised to retake that honor.

“One of the secrets to our success with keeping Call of Duty relevant and fresh for such a long period of time—so much longer than people thought we could—has been our willingness to let each developer do their own thing with the franchise,” said Eric Hirshberg, CEO of Activision Publishing. “There are certain core principles that the developers all share in terms of the way the game feels and the way you move through the world, the balance of the game and 60 frames per second gameplay. All those things are shared across the three studios. But then in terms of the creative expression, each studio takes their own personality and applies it to the franchise.”

Sledgehammer Games co-founders Michael Condrey and Glen Schofield bring extensive experience in interactive storytelling, having launched the horror third-person perspective franchise Dead Space for Electronic Arts in 2008 after collaborating at EA on the James Bond video game 007: From Russia with Love. Founded in 2009, Sledgehammer Games cut its teeth on the first-person shooter franchise, helping Infinity Ward develop Call of Duty: Modern Warfare 3. After that game became the fastest-selling entertainment title in history, Sledgehammer continued to work on DLC (downloadable content) for the game before starting work on its first original title, Advanced Warfare.

Set in 2054, the new game’s single player campaign puts players in the boots of Private Military Corporation (PMC) soldier Jack Mitchell (played by actor Troy Baker). The former U.S. Marine joins up with Atlas, the world’s most powerful PMC run by CEO Jonathan Irons (played by Kevin Spacey), after losing his arm and his best friend in a battle against the terrorist organization known as the KVA. The game’s story spans the globe as the plot unfolds to reveal Irons as a formidable antagonist who ends up wielding more military power and technology than entire countries.

Condrey said the role of Irons was written for Spacey, long before the actor agreed to dedicate a huge chunk of time over two years to the full performance captured acting that would bring the character to life. Sledgehammer Games shot the campaign action on the same Los Angeles stage with the same camera sets and technology that James Cameron is using for Avatar 2.

“That has really elevated the performances and the end-game representations of our characters,” said Condrey. “Fans are going to see nearly photorealistic performances with the actors in this game. Interactive storytelling is a great opportunity for Call of Duty to really go after performances and storytelling that we haven’t seen before on next generation consoles.”

While the game’s story does elevate the Hollywood thrills and epic action sequences, it’s the multiplayer gameplay that keeps fans captivated for a full year until the next COD game launches. Many of the new gameplay mechanics—including the introduction of Exoskeletons that meld man and machine for super-powered abilities such as bionic jumping, built-in shields and cloaking—translate to a vastly improved multiplayer experience. Condrey said all of the game’s technology, including directed energy guns that shoot powerful lasers that slice through anything in their path and the Pitbull armored vehicle that protects troops against IEDs (improvised explosive devices), is based on real weapons that are being prototyped today. Perhaps the most fun new toys are the jetpacks that offer timed aerial combat.

Schofield believes dynamic events that occur within the multiplayer maps will also enhance the replay value of the game both for fans and for the eSports teams that vie for $1 million every year as part of the Call of Duty Championship that Microsoft MSFT and Activision host. Now players will have new ways to strategize thanks to timed in-game occurrences like a tsunami that wipes out the low ground of one multilevel map and a working bio lab that features a crane moving huge canisters that can be shot at to fall on opposing players in another map.

Advanced Warfare also introduces more customization in the multiplayer through Loot Supply Drops, which come in three classes and offer players new weapon variants, character gear, and special one-use opportunities like Double XP (experience points). Players who buy the Season Pass for $50 will also receive a Zombies Mode for fighting against the undead, along with four multiplayer content packs that will be released throughout 2015. All of these ingredients should deliver the needed burst Activision could use this year for a franchise that has evolved from World War II battlefields to futuristic fighting across the globe (and in the case of last year’s Call of Duty: Ghosts, even outer space).

“Call of Duty is still one of the biggest franchises in gaming, so real growth is going to be relatively hard to come by, especially while the newer consoles are still growing their own bases,” said Mike Schramm, video game analyst at EEDAR. “The real goal with Advanced Warfare will be to get the Call of Duty faithful excited in a new title within the franchise, and to bring back dedicated Call of Duty fans who may have focused on other titles like Titanfall or Battlefield 4 over the last year. Call of Duty: Ghosts was definitely a huge title last year, and so the goal is to retain that audience and make sure that Sledgehammer can deliver with a brand new take on the franchise this year.”

While Spacey will help generate even more mainstream publicity for one of the most recognized video game franchises in the world, at the end of the day it’s the gameplay experience, especially the multiplayer offering, that will dictate success. With its interesting take on the future of PMCs and the brilliant new weapons, vehicles and gear that changes the way gamers will play the single player, co-op and multiplayer game; Sledgehammer Games delivers a worthy, and fun, new entry in the Call of Duty franchise. It’s just the shot in the arm that this perennial shooter franchise needed to reinvigorate the fan base during the busiest time of the video game year.