DerykThere is a great little recap in the DM materials for this campaign. At this time I think it is essentially spoiler-free because you have determined the link to Sarshan and the reason Megan was being threatened. So I’ll post it here for your enjoyment and illumination:
The shadar-kai arms dealer Sarshan has grown wealthy and powerful through his shadowy dealings. Over many years, Sarshan built up a vast, invisible mercantile empire supplying weapons, intelligence, and mercenaries to anyone with sufficient coin. Sarshan’s success (and continued survival) hinged in equal part on his clients’ discretion, his duplicitous nature, and his ruthless cunning.
Sarshan is cautious, and his desire for anonymity is such that he has walked away from numerous deals that presented an unacceptably high risk of exposing his operation. However, one of Sarshan’s trusted lieutenants, the dark creeper Modra, betrayed his master when he supplied the orc war chief Tusk with arms and equipment for his attack on the folk of the Stonehome Mountains. Tusk’s subsequent defeat brought the PCs into direct contact with Sarshan’s operation for the first time.
Subsequently, in “The Shadow Rift of Umbraforge,” the treacherous Modra attempted to slay the PCs. Pursuing their assailant to the Shadowfell, the party discovered the shadar-kai’s fortress—the isolated citadel of Umbraforge. Its resultant destruction earned the PCs Sarshan’s relentless ire.
In the aftermath, another of Sarshan’s schemes was stymied in “The Temple Between.” The githyanki war leader General Zithiruun, a valued client and ally of the shadar-kai, was slain attempting to capture Overlook. Sarshan had worked with the disgraced githyanki for some time, funneling troops through the network of portals scattered across Elsir Vale and coordinating the assassination of troublemakers. The relationship was a profitable one for Sarshan, and its loss irked the shadar-kai greatly.
These setbacks have badly damaged Sarshan and his carefully built operation. In an effort to salvage what he can of his power in the world, the shadar-kai has decided to destroy all evidence of his association with the githyanki.
Sarshan has recently become aware that Megan Swiftblade, leader of the Freeriders, has discovered his association with General Zithiruun. Assassins sent by the shadar-kai have attempted to silence the Freeriders, but have succeeded only in forcing Megan to flee to her home village of Talar, near the town of Brindol. There, she has thrown herself on the mercy of an old family friend, the sage Falrinth. As the adventure begins, Sarshan’s servants have caught up with Megan and are about to unleash an indiscriminate assault on the village.