ENVIRONMENTALISTS ACCUSED IN ARSON/MURDER INVESTIGATION - When a nearly completed upper Westside high-rise is torched, Detectives Briscoe (Jerry Orbach) and Green (Jesse L. Martin) take on the gruesome task of identifying the charred remains of a young woman caught in the blaze. The location of the building--a cherished former community garden--leads Executive A.D.A. Jack McCoy (Sam Waterston) and A.D.A. Serena Southerlyn (Elisabeth Rohm) onto the trail of a group of environmental extremists who may have taken their passion to a horrifying extreme.