The first is that you’ve basically given the party a mission briefing and a dossier file to work from, al a classic espionage setting. This normally works because characters are already a party with a chain of command through some form of Agency. You mention an NPC told them to stick together – this would be a breach of such command structures, and see the PCs “burned” or disavowed by their agency – there would most definately be some form of recrimination from their handler and higher-ups for this attitude.

If you don’t have such an agency in place, and it sounds like you don’t unless you want their gods to get in on the act (I think Mike wrote an article of limiting divine power, but this is probably one of those times when unlimited divine power works wonders) – you should probably readjust your adventure set up, so that there isn’t just one “file of clues” the whole party has access to, but rather each member of the party has access to a different clue and therefore they need to work together to find out what’s going on. Even such a breifing session where they discuss their clues could bring the party together, especially if the clues are personalized to each PC’s background.

The other flaw is that you are setting the adventure in a city, and in many cases, unless you make the city dangerous – it is normally a place where the PCs can split up into smaller groups to achieve their individual goals. One way to do this is to provide an encounter or other situation which shows them that city is dangerous, and the adventure is here, and not in the wilderness or some other dungeon, or elsewhere they might be used to. If there are adversaries in the plot, have them attack the PCs while they are together in the café to make them realise that there is safety in numbers.

You could even consider having the PCs framed for the incident, and hunted down by the police, giving the PCs a vital survival incentive to stick togther, if only to clear their name. It’s not a good idea to railroad the PCs into set actions, but you can steer them by shaping the world around them, so that their only real choice is to work together.

Whatever you decide, stick to your guns, and make sure you get feedback from your players. You’re supposed to be making the game fun for them, so while it may be very tempting to suspend their character’s priveleges (the Lord loses political immunity, the banker loses his money, the MI5 agent get’s burnt, and the socialite is ostracised by high society, for example) this may simply ruin the game for them. However, if you do it right, and give them the ability to regain these features, and use them, while restructure some of your ideas of how to run a game to meet what they want to do, this can work really well and provide your campaign and the party with the start it needs to unify them for future adventures, and prove that you are not such a green GM after all.

So first and foremost, check out why they want to play loners, rather than forcing them to come together. Such groups tend to prefer games like Vampire and Shadowrun, rather than the overly heroic tones of D&D, and if this is what you are used to, trying to force a group of people that prefer to play individual characters can break a GM and their plans.

I asked one of the regular GMs at this gaming group why they put up with this style, and they said they enjoyed it. They would have a loose plot, and let the PCs improvise the action. They would arange encounters and elements in their head so things could be run independently or together, as the action dictated, and allowed the PCs time to go off and pursue their own goals and cause trouble. He often has a twisted way of making the actions of one PC on his own affect another, and eventually draw them in together for the big climax when they were ready.

Sure, it can be exhasuting, and the PCs get smaller amounts of time in the limelight. This si the sacrifice they make for being alone. This alone will often force the PCs to start working together, just so that they get more screen time – if everyone is getting 10 minutes for a scene or so, then those who are sharing a scene would get 10 minutes each, or a 20 minute scene – this can be rewarded by allowing them more time if they deserve it.

Your role as GM is to make the game fun for everyone involved, including the players, and this means compromising what you find fun with what they find fun. There is no right or wrong way to GM, because every group will have a different definition of fun.

Watching TV taught me early in life that the best way to set up a comedy of errors is to contrive a reason for people to refuse to communicate, and that’s exactly what you get when a GM can’t or won’t be up front with his players about his needs and expectations. Just as it’s a GM’s perogative to choose the rules and setting he’s willing to run, it’s his perogative to choose the amount of party cohesion he’s willing to accept. There’s not a blessed thing wrong with saying, “Look, guys, we’ve had some fun with this, but keeping up with all the different directions your characters take as they scatter to the wind is exhausting for me. Concoct whatever reasons you like, but I need your characters to actually coalesce into a team if I’m going to keep running this for you.”