Covert Action puts the player against a series of terrorist conspiracies, one after another. Each time you start with a vague, undefined yet very present ticking clock working against you, maybe a handful of clues of varying value, and all the air travel the Agency can afford. From there you're expected to draw whatever conclusions you can from what little is known and then hit the ground running. Sometimes that's easy. "We know this guy is involved, here's his photo, he's in Brazil. Traffic analysis says the Shining Path is making huge money withdrawls." Sometimes you have to go in a bit blind and feel around. "Here's a codename of an otherwise unknown enemy agent we think is somehow involved. A car was stolen three weeks ago in Europe. Good luck?"
Gameplay consists of a series of minigames - there are top down stealth / shooter sections, circuitboard design sections where you swap out chipsets to activate your trackers while avoiding triggering alarm nodes, cryptograms to break captured message traffic, 'follow that cab' tailing / driving encounters. Each has a wide range of difficulties that scale with the 'threat level' you chose when you started playing, and you're given a 'specialty' when you start the game that makes a particular mini game of your choosing easier. Defeating a conspiracy gives you the option to step up a difficulty level on the next operation.
Although the stealth/shooter bit is unavoidable, the game does a good job giving you ways to work around any other minigames you don't enjoy or have difficulty with. Trailing a car can usually be bypassed by placing a bug on it instead. Crypto breaking can be automated, although this burns time pretty aggressively, or you can just track down the sender / recipient and 'ask them politely' what it says. Because of how clues are handled, you don't have to follow up on every lead, and might not have time to anyway. I personally hate the driving sections and can still enjoy Covert Action - I just avoid them wherever I can and just fail them right away when I can't.
Failing a minigame always comes at cost, but never out and out loses you the game. If you get shot up you'll be taken hostage and either have to escape (which takes time) or agree to give them enough info that they can inflitrate the Agency with a mole. (Mole hunts are another aspect of the game - distractions from your actual mission, but important to avoid being ambushed and the enemy tracking your movements.) Setting off alarms makes the enemy call in extra security, complicating future operations. And all the while the Conspiracy continues to develop.
Each conspiracy has a chain of events the enemy needs to complete to be successful, and you can break the chain anywhere. Steal the bank plans back and they won't be able to proceed to the bank robbing stage. Arrest the paymaster and the mooks will stop coming in to work. Once they know they've been bested, named enemy operatives will disappear into the shadows, biding their time until they can strike again. "Masterminds" lead each operation, and while your medium-term goal is to stop the terrorist attacks your ultimate goal is to take each Mastermind down so they can't keep launching these operations. This gives each session a nice range of how things can end - you can lose and innocent people die, you can stop the conspiracy while learning a little bit more about the mysterous person behind it while they escape, or you can shut down the whole institution by lopping off it's head.
It's a five out of five for me. Lots of ways to play it, in terms of difficulty level and what kind of balance you want for the minigames. You can play for an hour to just efficently stop an attack, or buckle down for a few hours and take down an entire international terrorist organization. It runs on a potato. I've never had a bug playing this across four computers and multiple years. My only caveat would be that I think if you didn't enjoy multiple minigames, or disliked the sneaking / shooting sections, you wouldn't have a good time. If you're into older games, though, you should be okay, as each of them (possibly excepting that darn driving game) is well put together and fun in it's own right.
I really want a remake of this. It could even be in spirit and not in name to bypass IP related expenses, the ideas here are so broad it would be impossible to C&D a modernized semi-clone without trying to claim copyright to the entire genre of spycraft fiction.
