It's come to this: you're having a torture-induced flashback to a time when you were told a story by a guy who is himself having an exposition-induced flashback to a time when he was shooting some people behind crates, following an NPC, and calling-in mortar strikes. This is what happens when Call of Duty tries to do a psychological thriller.

You're Alex Mason, a protagonist completely unrelated to Red Faction: Guerrilla hero Alec Mason, though he does happen to have the same square jaw, grubby stubble and gormless stare. In story terms, that means you're a hardened agent of a Special Operations Group carrying out classified objectives for America's interests around the world in the 1960s. In game terms, it means the NPCs you follow into battle are shouting “Get on the machinegun, Mason!” instead of “Get on the machinegun, Ramirez!”

"No! No more shooting Anatoly! Not after last time!"

CoDBlOps, we'll call it, is by Treyarch rather than Call of Duty creators Infinity Ward, but it wants to be a film just as desperately as their Modern Warfare games. The upside of that is several properly spectacular scenes: some of gaming's most exciting Vietnam vistas, slowmotion breaches through plate glass windows, base jumping off snowy cliffs, and various heavy things very nearly crashing into your face. Its set-pieces are as colourful and varied as Modern Warfare's, and frequently a little nuttier: you're sometimes given control of the vehicle involved, and the stealth ops motif lends itself to sillier gadgetry.

The downside is that it punishes you any time a scene doesn't play out as the director intended.

Your team is fleeing an avalanche. An enemy with an RPG pops out, so you shoot him. No dice: he's invincible, because he hasn't played his part in this scene yet. So he fires his RPG at the walkway you're on, beneath the guy in front of you. That guy's in front of you because if you try to run ahead of him, you're blocked by an invisible barrier. So the guy falls through the gap, and so do you. And if you weren't near the gap, you're teleported there to make this scene work.

Your friend is lost but you manage to pull yourself back up onto the walkway, on the wrong side. If you take a run-up to jump across, the game ends with the message “You failed to stay with your team!” You have to jump practically on the spot, or you'll be too far behind your comrades for the next scene to work, so the game simply ends.

For every great set-piece, there's at least one unforgivable mess of mis-scripting. One mandatory stealth section expects you to run out into the light and kill a guy in a potentially exposed area, without prompting. If you don't, even if you stay in perfect darkness next to your guide and no one sees you, it claims you've been spotted and guards pour in until you're dead.

All of the last four Calls of Duty have taken this attitude, but HakeBlips is barely interactive. It's like being in an action movie, certainly, but one where the writer won't tell you the script, the set designer puts perspex cubes in your way if you don't go where he wants, and the director yells “Cut!” every time you fail to read his mind.

Here's an idea, guys: make a fucking film. Get it out of your system, and come back to games when you're ready to give the player even the illusion of control.

Never fly in a vehicle that is mostly door.

Between the set-pieces, SharkBlimps is exactly the same shooter we've played through twice already in the Modern Warfares: short, controlled bursts with interchangeable assault rifles at B-movie baddies who tuck themselves behind crates, then sprawl theatrically across the floor when you finally clip them. You're taking hits! Duck down until the jam clears off your eyeballs. A grenade! Press G to fumble with it uselessly until it explodes, or move slightly and survive. We have fire support! Press 6 to target the gunship/ artillery/airstrike. A door! Wait for an adult to open it for you.

The only tweak is that the assault rifles are marginally less interchangeable now: apparently every goon, guard, trooper and agent has been a contestant on Pimp My Piece, so whatever rusty slugchucker they were packing turns out to have a scope, custom mag, silencer or Sellotape reloading system. It's almost like RPG loot, and it's fun.

You get incendiary shotguns, explosive crossbows, chunky revolvers. It's just a shame all this gonzo technology, and the whole black ops theme, doesn't relate to what you spend most of your time doing. The bungled stealth sections are brief lead-ins to the same shooty/shouty all-out war that's been getting increasingly lifeless with each game in the series.

Second worst way for a Castro lookalike's career to end.

If all its bits worked, PrawnFlaps would be worth about 75%. They don't. It's the first game since Elemental that I've had to install on three different PCs to progress. On one the game simply hangs during a certain cutscene, on another the very next mission roots me to the spot at a checkpoint. And restarting the level set me two levels back – ones I didn't much enjoy the first time.

It's worse in multiplayer. Server disconnects, lag spikes on good connections and total lock-ups are so frequent that it's unplayable for some of us in the office. They're only occasional on my main machine, so I've played enough to see that the technical problems are a real shame. Without them, this could be the best multiplayer Call of Duty in the current generation.

The game uses a currency system to let you choose which upgrades, equipment and perks to unlock as you progress. Having more choice, and a steadier flow of upgrades, ties the item system more tightly to the general business of deathmatching.

You get to fly and shoot in this section. So who's that guy?

The items themselves have a spirit of fun: the explosive remote control car is as hilarious to flee as it is to use. And while they're sadly restricted to wager matches that cost in-game currency to play, there are some nice new game modes. The best, Sticks and Stones, gives every player a crossbow with explosive bolts, projectile knives and a throwable tomahawk: get tomahawked and your score is reset to zero.

It's still grossly unfair, of course. CoD online is a great game waiting to be let out from the wreckage of Modern Warfare's disastrously stupid bit of design: giving the players who already have the advantage of skill and experience the added advantages of better guns, more damage, more powerful perks. And – when they inevitably achieve a streak of kills – a fucking helicopter to kill everyone on the map for them.

What saved the last Call of Duty, Modern Warfare 2, was its brutal co-op missions. FlounderChops doesn't have that – instead it revives the incongruous zombie defense mode from World at War. It's a slow, unsatisfying attempt at a genre that's been done masterfully by both Left 4 Dead and Killing Floor; nothing like as tense or exciting as just playing a Call of Duty game in co-op.

If Treyarch's goal with their Call of Duty games is to imitate Infinity Ward, they're finally doing an impressive job. The shooting is as dull, the scripting claustrophobic, and the set-pieces try just as hard to distract from both. But without a great co-op mode to back it up, without a startlingly fresh setting, and interrupted by regular technical screw-ups, Call of Duty's bluff and bluster has never felt so hoarse.