When an award-winning foreign journalist reveals the existence of an Amsterdam-based "knot shop" that employs and enslaves young girls as laborers, the private security firm Rutherford Risk is hired by a philanthropist to find it and shut it down. David "Sarge" Dulwich, John Knox's former boss, knows that Knox's culture and combat training plus his sympathy for the abused make him right for the job - balanced by Grace Chu's more subtle skills.