From Introduction:
While traveling through Barsaive, the group encounters an adept seeking their help to dismantle a slave ring. The adept provides them with information about an inn where travelers are abducted, and information on the Theran slave ship that transports the abductees.
The adept is in fact a member of the Keys of Death (Secret Secret Societies of Barsaive, p. 93-99), who has a grudge against the ship's crew. He views the group as helpful pawns to tie up some of his loose ends. The intelligence provided to the players is good, but the assassin is not planning on letting anyone but him walk out of this event alive.
Optionally, a shortened version of this adventure would eliminate the entire assassin angle, and just have the group stumble upon the slave rings themselves.