The Missing Pin (5E)

From the publisher's website: At the confluence of the Great Amrin and Glimmrill Run rivers sits the small town of Gumspur, a small backwater town known only for its convenient location and its only real export, pottery. So, when an audacious theft victimizes one of the leading families of Gumspur, a group more capable than the local constabulary is needed. On its surface, what looks to be a simple theft conceals a much deeper and much more dangerous conspiracy.