“The dead are crying out for justice,” Dith Pran, a survivor of Cambodia’s Khmer Rouge regime, pled in Children of Cambodia’s Killing Fields, imploring future generations to tell the story of the lost. Cambodian Rock Band, from playwright Lauren Yee, answer Pran’s call. It begins with another Khmer Rouge survivor and his return to Phnom Penh, where he watches his daughter, a lawyer, prosecute a notorious general. The trial triggers memories, transporting the father back to the 1970s, a time before genocide wiped out the country’s artists and intellectuals. Live performances of retro Cambodian music come courtesy of the contemporary band Dengue Fever. —C.J.F.