killing spree where he handcuffed his victims, then strangled them until they stopped breathing. a technique he demonstrated on assistant state's attorney larry finder. >> and he reaches into his pocket and takes out his rosary. he said to larry, put your harm in here. and larry just kind of naturally flinched. and he said, relax, larry, i'm not going to kill you. so larry put his arm in. and gacy demonstrated on larry's wrist how he used the rope to kill these kids. >> these young men, they suffered before they died. >> yeah, it was a -- it was very brutal. these were sexually motivated crimes. he would rape these boys prior to killing them. >> boys including his missing employees john butkovitch and gregory godzik. the owner of the class ring,