Hello
Maybe you could center the game around the machinations of 'Colonel Apis' ?
http://en.wikipedia.org/wiki/Dragutin_Dimitrijevi%C4%87
http://en.wikipedia.org/wiki/Assassinat ... _Ferdinand
The codename Apis (Bee) could have been more than that. Maybe he has some mind-controlling powers (so him being the queen bee) and his henchmen act like a hive mind? Or/and maybe he really is some form of shapechanging bee-demon? Maybe the man himself is only acting the (un)willing vessel of the demon (explaining why he can be executed later)?
His plans of uniting the southern slavs could have the darker purpose of creating a slave-nation under his control?
Unless you want to change history, you might consider building a 'bigger' threat than the World War that followed, to give the players the sensation of having succceded in averting the 'greater evil' (Reign of the Red Death).
As one of Apis other codenames was 'No.6' maybe he also is one of Pontanegro's 'El Siete', one of the Seven Fiends who answer directly to the Red Death?
As for your old, dead apothecary...maybe he for some reason knew of Apis and his plans and was brutally killed by demon Apis or one of his monster minions because of his knowledge, but his spirit was strong enough to animate his chopped of hand to write the letter AND deliver it. You could use the hand as a recurring 'index finger' when the PC's are missing something.
Maybe he also knew how to create an antidote (let's say out of Honey or that Gelee Royal stuff) to the demon's mind-controlling powers?
Following the bee-story you might bring an old time favorite: Sherlock Holmes, who became a bee-keeper in his old days. Maybe there was a supernatural reason for taking up this hobby? Maybe the PC's find letters within the possesion of the apothecary that are a correspondence with Holmes?
As Holmes is pretty old by then, he might become the supernatural sage the PC's will keep around (and will have to protect as well)?
Just make sure he has spare time for 'His Last Bow' on 2 August of 1914
As you will have to bridge almost 6 month from Vienna to the assassination in Sarajevo you might consider to first confront the group with a smaller group of henchmen revealling little about Colonel Apis first. Maybe the group is part of a larger network? Groups of cultists/beekeepers preparing a larger ritual. Maybe they will use the bees to deliver demonic poison (Think of the bees delivering the alien virus in X-Files) either to further Apis mind-control or transform the humans into willing servitor-creatures? Maybe the bee's queens are feed with Apis his blood (giving the players a tool to later use to banish Apis in the process)?
Best Wishes
William
The Gem of Amara...
Official sponsor, of my killing you.
))
That's because the smilie doesn't display on your browser, wisecracker.