"If the front door is opened," Barris said, "during our absence, my cassette tape recorder starts recording. It's under the couch. It has a two-hour tape. I placed three omnidirectional Sony mikes at three different--" "You should have told me," Arctor said. "What if they come in through the windows?" Luckman said. "Or the back door?" "To increase the chances of their making their entry via the front door," Barris continued, "rather than in other less usual ways, I providentially left the front door unlocked." After a pause, Luckman began to snigger. "Suppose they don't know it's unlocked?" Arctor said. "I put a note on it," Barris said."