On a conceptual level, it's rather brilliant, sowing just the right amount of suspicion into the relationship between players. As well as keeping an eye on the gun-toting foes around you, there's a constant pressure to keep an eye on your own team, watching to see if they're sloping off in the thick of the action to fulfil some personal mission.
Where the idea falls apart slightly is in the execution. There's just not enough at stake to make this secrecy worthwhile. All you earn are points that go toward unlocking extra weapons, and once you've unlocked all the weapons, they're available across all characters forever. So once you've got them all (probably offline), the whole "secret agenda" element becomes rather redundant.
It's also largely pointless in single-player, as you can easily leave your AI partners waiting at a checkpoint before dashing back to collect anything important. Finally, the collectibles appear in the same place every time, meaning that in the long term everyone will know where everything is, and know immediately why a certain character is shuffling suspiciously towards a certain corner.
It's a shame, as the "secret agenda" idea should have been The Cartel's defining feature. Instead, it's a curious but ultimately worthless addition that feels half-developed.
At least the game has robust if unspectacular combat to fall back on. This is very much the sort of unfussy, old-school run-and-gun shooter that Duke Nukem Forever was supposed to be.
There are few concessions to realism as pistols crack off headshots at long range with iron sight aim, cars explode after a few bullet hits and enemies pour out of doorways and alleys before milling about, shooting and lobbing grenades like angry fairground ducks.
Control is frictionless, your character skating around on all terrain in true Quake style, but for all the game's many faults the core mechanics are solid and enjoyable. In the moment-to-moment gunplay it's entertaining enough, and good pacing keeps it engaging over the long haul.
There are even brief driving sections, blighted by floaty control and some hit-and-miss signposting, but fun enough to serve as buffers between the more traditional FPS slaughter. These bits are best in co-op, as two players get to lean out of the windows and blast away at pursuing SUVs. In single-player, you're almost always the driver, which leaves your survival in the hands of the less competent AI.
Sloppy production values also conspire to obscure The Cartel's better qualities. The subtitles only occasionally match what is being said and dialogue cues often trigger early, leaving the characters talking about things the player has yet to see or speaking to people who aren't there. Partner AI has a weird habit of shouting "left!" or "right!", but these exhortations rarely match up with where enemies are coming from.
It's a workmanlike experience, then, but not without its charm. The Call of Juarez series remains hard to pin down, both in intent and appeal, but that's not to say there's nothing to enjoy in this latest effort.
In the rush to follow the Call of Duty template, there's certainly a hole in the market for an unpretentious, all-guns-blazing fragfest. If The Cartel is too shaggy around the edges to fit that hole precisely, it at least comes close enough to warrant a visit from players eager to give their trigger fingers an old-fashioned workout.