PROPOSAL 4: By Ludo
The Alumni of Seal Team 5
Main Threat: various groups of Ghouls and related creatures
Acts: somewhere between 3 and 5
Back during the Vietnam war, the US Army encountered ghouls during their fights against the vietcong near the Cambodian border. Those "cave cannibals" demonstrated so much stamina and strength (not even counting the tactical advantage given by being able to dig your way around an enemy) that PROJECT SUBTERRANEA was funded by MJ-12 after the war, based on the couple of subjects they managed to acquire.
Seal Team 5 was formed by all the solders who volunteered for human testing of this new "super soldier"-marketed project. That project was a failure, however. Some subjects died horribly, some others went insane, and the rest didn't seem to show any signs of ghoulish abilities.
When the son of a Seal Team 5 member starts eating his girlfriend, DG gets involved and unravels a web of consequences for a 30 year old project… it's up to them to clean MJ-12's mess, but in doing so they end up facing dangerous enemies, forming impossible alliances, and getting knee deep in the conspiracy.
This first scenario is pretty easy, especially since at least 2 NPCs can help the players. This is so that a new group can find their groove (especially when players are not used to investigation-based adventures) and slowly get into the DG conspiracy (at the end, the players are enlisted as friendlies or agents, depending on how well they performed). The other scenarios slowly ramp up their involvement in DG, and the last act is a big free-form scenario with lots of factions and NPCs with various agendas. The goal is to establish DG as a bunch of "good guys" fighting evil, even though this often involves morally difficult decisions. It would take a second campaign for the players to actually realize DG is not official and can be pretty evil sometimes too.
The campaign can be stretched or shortened according to your needs: scenarios can be added (each one focusing on a different Seal Team member or related individual) between the first and last scenarios, and each scenario can send the players in a different area, on an adventure with different themes and moods.
Act 1: Teenage Wasteland
One of the Seal Team 5 members retired from military service to raise his family in a nice suburban area, but after a few years he started experiencing "changes" in his behaviour, physical abilities and, above all, eating habits. It culminated in an unforgivable event that sent him running away — and he's been hiding ever since. Unknown to him is the fact that his son is also experiencing the same changes, only he mixes everything up with the emotional rollercoaster of being a teenager.
When a couple of mutilated bodies turn up in the same area, and the wounds have human teeth marks in them, some flags go up inside DG. If the players are already DG agents, they are sent to investigate the case, if possible (depending on their profession) by replacing the current officials in charge (e.g. the FBI taking over a local police case). Otherwise, they just do their own parallel investigation. If the players are not DG agents, they are the actual people assigned to the case, but a mysterious "Agent Osborne" may contact them at some point.
The Seal Team dad can also contact the players, acting like a "shadow informer".
For added complexity, a test sample of the saliva found in the victims' wounds could have been sent to the FBI lab. The synthetic compound would raise alerts inside MJ-12, which would then start watching the players from far away.
Act 2: Your First Opera
After the first case, Osborne contacts the players with a list of Seal Team members, and some leads to find one of them. He was last seen in one of the Bible Belt states. The player soon realize he's built a Christian-based cult around him with a very literal interpretation of "eating the flesh of Christ" (most members have "offered" one of their limb to their messiah). There's an unusual pattern of kidnappings around the cult's farm, too, spanning all the way to the neighboring states, as the cult members try to hide the fact they feed on travelers.
The cult leader (the Seal Team member) actually tried to understand more about his transformation, and during his travels he learned about the magical abilities ghouls can get access to. He is currently attempting to shift his farm — and his cult — somewhere half-way to the Dreamlands in order to stay hidden from the authorities.
This mission results in the players getting more information about the ghouls, especially with the books and notes their can seize from the farm (if they didn't blow it up before searching it first). Of interest are some of the cult leader's contacts, which include other Seal Team members, but also a couple other ghoul communities elsewhere in the country, and a few other Mythos-related factions (if needed for future scenarios).
Act 3: The Untimely Death of Mr. Osborne
When Agent Osborne calls the players once again asking them to meet him in a quiet part of New Jersey, they think it's gonna be another quick briefing with lots of omitted information, a cryptic manila envelope, some paranoid recommendations, and the code to a greenbox for them to use during an upcoming investigation on a 3rd member of the Seal Team 5. But instead, Mr. Osborne is missing.
After a bit of searching, they find Mr. Osborne's body: he blew his brains out with his own gun. Finding his notes, they realize he was indeed gathering intel on a Seal Team member, but the trail ends abruptly after he started looking at a few funeral homes scattered around the state, all owned by the same people.
It turns out this is the first occurence of any DG agent outside of Cell-A and Cell-N to discover about ghouls being able to take the appearance of another human being (see the DG sourcebook for info on Cell-N). Cell-A kept that information to themselves, like the assholes they are, to help keep cell N's integrity. They figured they would share the info with the other cells when necessary. But when agent Osbourne realized it, it was too late — he was in a tight situation with another hungry ghoul. No time to ask Cell-A for information. He knew, however, that DG would be compromised and decided to sacrifice himself. The players will realize soon enough that this kind of sacrifice is pretty useless, and that Cell-A is really a bunch of assholes.
Anyway, that's when the players get all promoted to full DG agents, one of them being also promoted to cell leader with a phone line to Cell-A and all the headaches that come with it. Time to grow up.
The case itself is what you would expect from ghouls: they own cremation houses and cemeteries where bodies are fed to their community, but also sometimes sold to a special clientele: humans that want to indulge in cannibalistic activities, either because they're fucked in the head, or because they have a ghoul-fetish somehow (which means they're also fucked in the head, by the way). Also, the ghouls have links to the local organized crime families in a way that leads to believe that ghouls may have infiltrated one of the nearby New York crime families.
This one will be a lot trickier to solve, obviously, and even more difficult to actually win: the enemy is not a self-contained organization like the previous case, and there's just too many ghouls and ramifications to hunt down. This is where the player's actions will start to have likely consequences in future scenarios, and this is where they learn the hard reality of fighting the Mythos: you can never completely win.
Act 4: The City That Never Sleeps
The previous case brought a whole new world of problems to the players — chief among them is that ghouls can look like anybody, and may have access to the Mafia's resources.
Following the lead to one of NYC's crime families confirms the players' nightmare: there are indeed ghouls in one of them. Worst, they realize that those ghouls are the "pragmatic" branch of a group called the "Heretics" — ghouls that believe they shouldn't have to hide and feed on rotten corpses, and instead should hunt humans and be their masters. Those guys are engaged in a secret war with the "Keepers of the Faith", old-school ghouls that live in NYC's underground, and could be made into allies (check Countdown for more info on all this, minus the Mafia connection). And then again, there's the problem of Stephen Alzis, who will be all too happy to mess with the players in order to stir this whole ghouls situation going on in his city one way or another. Or maybe he doesn't care and just wants to have fun… but even that could backfire.
This last scenario is obviously very big, and unlike the first couple ones, totally non-linear. It also probably ends with the situation blowing up in some way, and either half of the players dying, or Cell-A telling them to get the hell out before they do any more damage. In any case, it should have interesting ripple effects throughout the DG-verse, especially depending on MJ-12's involvement (I envision MJ-12's role in this campaign to be limited to optional sideboxes, for GMs that can handle more complexity).
MJ-12's optional involvement: they will find some interest in the players at some point, seeing how they seem to follow the trail left over by an old project of theirs. They are also newbie DG members, and those are the easiest to turn — or use in some way. In my game, one player became an unknowing spy for MJ-12, and this paved the way to a full front clash between MJ-12 and DG that happened in the second campaign… but as far as this 1st campaign goes, they're mostly in the background, with an occasional muscle intervention from one of their strike teams.