Call of Duty is obsessed with fear. But while Modern Warfare and its sequel exist as a paean to America's current socio-political nightmares, Black Ops chooses to tap into the nation's Sixties terrors: Cuba, the Vietnam War and, primarily, the ever-looming threat of Soviet conflict.

Part of Treyarch's current problem, then, is the format's inherent need for escalation. In a series defined by its rigid spectacle, and one that's already detonated a nuclear missile in your face and had you squeeze the trigger during a controversial airport massacre, there was always going to be a certain onus on the developer to come up with the next headline-grabbing scenario. And they certainly give it their all: within thirty minutes of Black Ops' start you've already shot a slow-mo bullet through Fidel Castro's noggin and escaped a Russian gulag. The series' most precious tactic is to whip its audience into stimuli overload with ceaseless audio-visual spectacles; while Black Ops offers up its own distinctive take on the formula, it's ultimately no different.

It comes as no surprise that the game leads you with gusto through its artificial scenarios, with mid-mission cutscenes herding you from each meticulously designed set-piece to the next while avoiding - though briefly acknowledging on occasion- the dramatic constraints of things like commuting, or the unpalatable taste of moments where things aren't exploding.

Treyarch manages to successfully avoid the jarring disconnection endemic of its previous work by, ironically, focusing on the same whooshing cinematic segues which World at War employed with such abandon. But where World at War's cast were lifeless husks for the player to fleetingly inhabit, its cutscenes far more concerned with style over any tangible substance, Black Ops revolves around a small cast of characters, going to extreme lengths to burn their names and faces into the minds of the player.

Most of the campaign is set in 1968, though events are primarily told via the flashback sequences of protagonist super-soldier Alex Mason, who in turn spends the game strapped to a chair while being pumped full of experimental drug cocktails. Briefing screens have been replaced with a grisly-voiced mystery interrogator barking questions at Mason, who then promptly recounts the sequence for him and, by extension, the player.

Much like the rudimentary stove I used throughout most of university, Black Ops' 15-level campaign takes a fair while to heat up - with some rote corridor-blasting exemplifying the initial stages - but it's also blistering hot when it hits its stride. Perhaps most interesting are the seeds of doubt Treyarch plants: Mason's skewed take on events are shown as foggy and imprecise, and his unreliable narration convinces neither the mystery interrogator nor the player. Unlocking the actuality of Mason's situation becomes the thrust of the experience, and when the curtain is finally lifted the conclusion is satisfying though predictable.

The supporting cast features Ed Harris as spooky spook Hudson, who at one point actually puts on a pair of sunglasses to show that it's time for action, and there's also the excellent return of Gary Oldman's beleaguered and world-weary Viktor Reznov - the requisite decent-ish Russian character to prove they're Not All Bad. This neatly brings us to the pantomime villains of the piece: a pair of (surprise, surprise) nasty Russians - Dragovich and Kravtchenko - and an unrepentant Nazi.

Though many of its narrative progressions are absurd, anchoring the proceedings to an identifiable protagonist helps to ferry the story onwards. Mason and his frequent travelling companion, Woods, are routinely subjected to torturous events: dangerous scenarios slice open muddied skin, knees buckle under the strain of exertion and blunt trauma is applied with alarming regularity, all accompanied with performance-captured expressions of pain and audible grunts. Their pain is definitely felt.

In forcefully unlocking the secrets buried within Mason's head (including the most important string of numbers since Lost ended) the game, like its politically-charged ancestry, actively trades in sentiments the USA would often rather not think about. Vietnam is a major stop-off point, for instance, and while the startling sights and sounds of a burning Hue city are remarkably impressive, those shocking images can't quite muster up the same evocative weight of Modern Warfare 2's suburban America reduced to rubble.

That's not to say Treyarch isn't teasing out its own contentious imagery. The developers' mercenary treatment of human life is typically grim, and its many gratuitous displays of violence proudly earn the game its 18 rating. A flashback sequence to World War II actually has you shooting Allied forces at one point, for instance, which should go down particularly well with Daily Mail readers.

The question with Call of Duty is not whether it's a fixed rollercoaster ride - it clearly is - but how effective that ride is - and a fair few of Black Ops' rollicking trips are on par with the series' finest. The sprawling jungles and dilapidated cities of the game's Vietnam levels are standout highlights, with the environments perpetually engulfed in thick black smoke. A late-game snowy jaunt hearkens back to last year's outing with Soap MacTavish, there's a solid nod to The Deer Hunter, and a trip to the Baikonur Cosmodrome allows a rocket launch - an image hugely indicative of the times - to become an iconic setpiece.

As for how you'll merrily blast away the reams of opponents along the way, the standard SMG and assault rifle pairing - truly a match made in heaven for modern developers - is mixed up by a hefty accompanying arsenal. Potentially anachronistic weapon selection is written off by your inclusion into the Studies and Observation Group; firing novelty guns like the explosive crossbow or the Dragon's Breath (a shotgun with devastating incendiary rounds) could be seen as ruining any attempts to build a delicate tone, if only they weren't so much fun to use.

Treyarch proves itself as a more capable developer since the immature outings of yesteryear, and things like World at War's blatant corridors have been neatly hidden within illusory wide-open environments. The ridiculous levels of enemy grenade spam have been significantly dialled back, though they still occasionally present a problem, and while the series' staple shooting galleries remain - by the seventh major outing of a series, to expect anything otherwise would be foolish - they're handled with a defter touch and a more confident execution. Ultimately, the developer has learnt to add substance to its overproduced spectacle, though it's a shame to see infinitely spawning enemies used to pad out some of the large-scale confrontations.

Still, many of the sections which stand out the most about Treyarch's latest campaign are its slower moments. Call of Duty has always been about as subtle as those people who type their Facebook status in CAPITAL LETTERS TO SHOW HOW IMPORTANT THEIR POINT IS, but one of Treyarch's main failings in both Call of Duty 3 and World at War was its ceaseless staccato pacing - a constant bang bang bang bang bang, which afforded no space for character or development. Magnificent explosions are all well and good, and Black Ops certainly has its fair share of those, but there's a pleasing nuance here that Treyarch's previous work somewhat lacked.

There are still problems with the narrative delivery, mind, such as how you're whisked from 1963 to 1968 without any discernible jump in time for your characters. President Kennedy also finds himself in the spotlight at the start, only for his assassination to be ignored until finding itself suddenly unearthed, years later, as a major plot point in the game's closing chapters. Still, at least there are no quotes delivered with ham-fisted sincerity about the horrors of war when you eat a stray RPG round.

By framing itself around an altogether more personal conflict than Modern Warfare 2's rendition of World War III: The Early Years, Black Ops' campaign never quite manages to muster up the sense urgency of last year's iteration. This latest Call of Duty is still a thrilling, ambitious and engaging campaign in its own right, however, with an obviously lavish budget and top-tier production values, but crucially Treyarch has finally shown it understands the rhythms and tics of the franchise that, over the course of the last year, has become its own.

It's impossible to know how Black Ops' take on multiplayer will cement with Call of Duty's mammoth online audience over time, but initial impressions are hugely promising. The time I spent with multiplayer allowed me to get just shy of level 19 - although I was also provided with a profile that had everything unlocked - and while that's not enough to make any bold claims about the future of the series, it was plain to see that - in a similar vein to the campaign - this is already a far more accomplished experience than Treyarch's previous efforts.

There are 14 multiplayer maps on offer, though that list will gradually inflate with premium DLC, and the initial highlights include Cracked and Havana - two levels absolutely destined to be the favourites of many for the next couple of years. The range is far more successful than World at War's bland selection, and the architectural and layout trends have clearly borrowed a few pages from Infinity Ward's design manual. They're equal parts indoors and outdoors, complex but never complicated, and orchestrated with enough ingenuity to naturally guide you into the action.

Simple modifications to the established formula have a profound impact on the end result. Deathstreaks are gone. Killstreaks no longer count towards further killstreaks, and the new CoD Points currency - doled out at about a tenth of accrued XP, and required to purchase items after being unlocked - allows you to buy that red dot sight as soon as you obtain your next weapon. Anyone worried about those bloody dogs will also be relieved to know they've been bumped up to an 11-kill streak, which turns them into an occasional horror instead of a frustrating plague. Alternatively, 11 kills can also buy you access to a pilotable Hind helicopter, so don't expect to see the mutts too often.

On top of that, regular attack helicopters now only patrol a (user-selectable) spot of the map, as opposed to dominating the entire level. The skies are, on average, far less occupied than before, but a barebones playlist is now available for those who'd prefer to be rid of them entirely.

Perks are, as always, split over three tiers and are mostly recognisable (with the odd name change) from their MW2 incarnations - the only all-new addition being Tactical Mask, which protects you from the new Nova grenade. More significant, perhaps, is the non-inclusion of Stopping Power and the massively contentious Commando and One Man Army. The remaining lot - running faster with Lightweight, holding your breath longer with Scout, reloading quicker with Sleight of Hand and so on - are now transmogrified into their Pro version, which confers a further bonus by accomplishing multiple challenges.

This seemingly never-ending trail of rewards and unlocks remains compulsive, though the slight changes are evidently geared towards refinement rather than revolution. The devil is in the details: the MP5K has considerably less recoil and bounce than its Modern Warfare 2 iteration, for instance, though its still duff at long range. You've also got weapons like the G11, which is an absolute monster but finds itself crippled in reload speed and available attachments.

On top of this, Treyarch has added a major suite of community-building features to reward dedicated players. Playercards are now almost entirely customisable by the user, so if you've ever fancied turning your red dot sight into a smiley face, well, now's your chance. Theatre mode, perhaps more usefully, allows people to preserve their finest moments and share them online. But the most exciting and immediate addition is Contracts, which allow you to bet CoD points on strictly-timed challenges - win x amount of games, get y amount of headshots - that you set for yourself.

If you've got a taste for taking such risks, you'll probably also love the new Wager Match mode. Here you gamble amassed CoD Points, instead of receiving XP, to potentially win big (or small; there's a mode where you gamble mere pennies) from a novelty 6-player free for all game; only the top three players will walk away with a share of the money. Modes are even selected randomly on bigger bets. One in the Chamber gives you three lives, a single bullet and a knife; Sticks and Stones dishes out explosive crossbows with aplomb, while also letting players "bankrupt" each other with tomahawks (Black Ops' take on the throwing knife); and Gun Game and Sharpshooter play around with a wider arsenal. The latter has everyone using the same random weapon for 45-second bursts, whereas the former has you incrementally progress through 20 weapons, changing your gun after each kill.

Wager Match is unlikely to dethrone Team Deathmatch as the series' premiere multiplayer mode, but that's clearly not its intention: this is a meticulously developed way to play some novelty games, and one that will prove invaluable for burning through some time while you wait for your friends to show up online.

Zombies mode makes its ever-controversial return, but once you get over the raucous tonal incongruity of headshotting the walking dead as JFK and Nixon, it exists as a self-contained co-operative survival mode - albeit one where you're constructing barricades and earning credits for new weapons while trapped in the Pentagon. Two maps are supplied on the disc, one with the aforementioned political figures and another which heralds the return of undead Nazis. The zombies don't stop until you're dead, and despite your eventual demise it's still a surprisingly enjoyable romp. A third map turns the game into a top-down twin-stick shooter, but while the gimmick is initially entertaining, the mode doesn't really have the legs to stand as anything other than a temporary diversion.

Treyarch isn't trying to reinvent the formula which made Modern Warfare 2 the most successful video game of all time, but it has laid down solid multiplayer foundations while adding a series of necessary and intelligent tweaks - which should be music to the ears of the game's many fans. A spectacular but silly single-player campaign rounds off the package, and while it comes without Modern Warfare 2's ambitious (but unsuccessful) attempt at carving out a political message, Black Ops offers its own thoroughly enjoyable romp through some entertaining set-pieces. I've considered myself a Call of Duty fan for many years, and I've held a deep-seated distrust of Treyarch since Call of Duty 3. No longer.