 The famed "bag over the house" episode (Rock Hudson later explained that the production company had way overspent the preceding episodes and had to do this one on a shoestring, with no additional sets and only six guest actors) features Mac investigating a psychotic killer who targets socially prominent people. The killer goes after Mac and Sally by drugging their drinks and calling up a pest-exterminating company, which encloses the entire McMillan house in a gargantuan, airproof and soundproof bag and starts pumping poison gas inside. Mac and Sally awaken and can t get out. The killer, wearing a breathing apparatus, is inside as well and taunts them as he did his other victims. He also has swiped Mac s gun just in case Mac decides to put up a fight. Mac must try to outwit the killer and alert the exterminators to shut off their poison pump and remove the bag before he and Sally suffocate. Rock Hudson remembered that this episode was a fan favorite.