The Crucible

Capturing one of their enemies Sue and Sam interrogate him and are almost killed when he escapes. However the information allows Sue to work out how the Changels were almost caught previously.
Unfortunately their effort to dispel the mystery of the original house fire is intercepted by the Administration and used against the Changel's families. Anticipated at each turn the Changels are almost caught. At the same time the Bruderschaft is using the distraction to launch a new plague.
Driven into a corner the Changels are ultimately left with no option but to fight.