I like the idea, the basis is reasonable and contains potential.
A few questons, however:
Why would Sadis, who appearently has no use for allies or friendships, especially those that may expose him, keep Gnome-y around?
Though we know he is grredy, does he have any characteristics that would cause him to do things?
Does Sadis have long term plans? Making a big hit? Getting married, settling down? Go to Comment
A circus is in town and while parading down the main street the animals suddenly break free from the cages. After surviving and assisting during the breakout the PCs are hired to help with the investigation. Who did this and why?