Beginning: The party hears tales of a large humanoid attack on Rokin, the capitol of Drucinia, a lawful nation. The raid included flying creatures such as griffins, hippogriffs and even a blue dragon along with a humanoid army. For a tie-in, one of the characters or NPC's should have ties to Rokin, thus leading the party to investigate. The rumors make it sound like the city has been burned to the ground and all the people are dead...
After the party gets to the city, it becomes apparent that the rumors of Rokin's near-destruction are greatly exaggerated. In fact, to someone unfamiliar with the city, they might not even know that an attack occurred. There are only a few damaged buildings, but the townsfolk are really rattled - so rattled that their tales are already ballooning way out of proportion. "I swear it was 5 dragons." "No, it was 10 if not more." "And 500 orcs." "More like 5000." "We're just lucky to be alive."
In fact, the force was only about 100 creatures total...
In Rokin, posted notices and town criers announce that the King of Drucinia died a few weeks earlier leaving no heirs. In his place, the acting regent, Agral Tymart has been convening with the Rokin council to select the next ruler. However, as this was transpiring, a powerful warrior, Dreth Caldan, and his forces raided the city, and stole the Drucinic Crown and Scepter. Until these are returned, the next king cannot be appointed. After consulting the Law Scrolls, the council has selected the next king, a half-elf (who is neutral and a strange choice as most Drucinic kings have been extremely lawful). Agral Tymart has offered a reward for the return of the royal items as well as the capture of Dreth Caldan.
Arrange a meeting between Agral and the interested party. He will give as many details as he can. He knows the force wasn't that large, but he doesn't know why Dreth stole the items. Agral knows Dreth somewhat and pleads with the party to capture him and bring him back for judgement as opposed to killing him. Agral suspects that Dreth had a good reason to take the items. He will explain that Dreth believes humanoids and other monsters are acceptable forces; they just need more supervision. These views are part of what makes him evil. His troops consist mostly of orcs, hobgoblins a handful of giants along with his flying mounts: griffins, hippogriffs and his personal blue dragon steed. These forces are extremely well disciplined due to Dreth's skilled leadership.
One of the councilmen, Akelor, will also meet the party as they are leaving. He will be much more vindictive saying, "This man must be punished. He has defiled the throne, sitting upon it as if he were the king. Do not hesitate to kill him." (Akelor is the only one to witness Dreth's throne room visit.)
The party will presumably set out to deal with Dreth. His base is a mountain keep at the eastern edge of Drucinia. It is heavily defended. The mountain terrain along with the defenses make a frontal assault nearly impossible.
During the overland trip, the party might catch glimpses of a grizzled old woodsman that might be following them. If they investigate, no trace of him will be found. If and only if a party member is seriously injured, he might emerge suddenly from the nearby trees and heal them. He will just as quickly vanish into the growth. He will not do anything else. This character is an addition to the original 1st adventure and will return in various forms throughout the Rokin Chronicles.
Near the mountains, the party will meet a (very) helpful elf who knows of a secret way into the keep. Below it is an ancient crypt occupied by various undead. Dreth knows about this, and has left them there as guards. He doesn't care if the party wipes out the undead. Once they get past the crypt, either allow the party to be captured or fight their way through Dreth's forces to meet him. His guards have orders to capture first, and kill only if necessary.
Dreth is powerful, and should be difficult (even impossible) for the party to defeat in combat. But, if they role-play the situation instead, he can be talked into returning to Rokin. He is somewhat evil, but he is also extremely lawful. His raid on Rokin was extremely selective, as he targeted the 2 items (which he believes are rightfully his). He is upset that some minor damage occurred during the raid. The guilty humanoids have been punished. He insists that he left a scroll on the throne explaining his actions. In fact, one of the councilmen was there...
According to Dreth, The Law Scrolls in Rokin prove he is the next king. (And he is right! This is due to a number of obscure laws and the order of titles in the situation of a king leaving no heirs.) One of Dreth's agents in Rokin notified him that something was amiss. But, the agent was discovered and killed before learning more. Dreth seized the crown and scepter to avoid losing the rightful title, since if another was crowned first, he would lose the claim. He returned to his keep to wait for vital information from other agents throughout Drucinia that will hopefully expose the plot. Fearing the party might be part of this, he will not reveal any information concerning the plot or his agents. However, he trusts Agral Tymart, so he is willing to accompany a group sent by him. (The crown and scepter are hidden in his keep, and he will not reveal their location. This is his only insurance at the moment.)
At some point after Dreth has agreed to return with the party, the elf NPC will attempt to kill Dreth. He is really an assassin, and part of an elaborate elvish conspiracy to seize the Drucinic throne. He will make an attempt on Dreth when the opportunity presents itself (i.e. he is alone with Dreth or with only 1 other party member plus Dreth). It is up to the DM whether the attempt succeeds. Regardless of the outcome, the elf will escape.
If the party returns to Rokin, and then questions Akelor via truth spells or similar means, the truth will come out. Akelor removed Dreth's scroll as well as hid and forged the Law Scrolls that would prove Dreth is the rightful king. If pressed, Akelor will reveal that he did not act alone, but doesn't know all of the people involved. He does know that the half-elf king-to-be is aware of the conspiracy. The death of the former king was also orchestrated by someone involved (the elf the party met earlier). The conspiracy also involves some of the elvish ambassadors in Rokin.
If Dreth was killed, he will be raised from the dead by priests in Rokin. Dreth will send messengers to his keep and his dragon mount will return with the crown and scepter. Then he will be crowned as the rightful king.
Note: Both the Crown and Scepter of Drucinia are artifacts. Their true nature will be revealed in Part 4.