Tumbleweed - Grijpstra & de Gier, Bk 2 Author:Janwillem Van De Wetering Maria van Buren is found dead in her boathouse on an Amsterdam canal. Grijpstra and de Gier must solve the murder. Her regular clients have sound alibis. Before the murderer is caught the detectives and their commisaris will investigate allegations of black magic, travel to Curacao, and pursue their clues to an island off the coast of Holland.