In non-stop action taken from one single camera, Laura opens the front door, giving Rob "his freedom". Rob saunters out the front door. Laura closes the door then reopens it and is surprised that Rob is gone from view. Laura goes out the front door. The camera then pans to the right to reveal Rob sneaking in from the back hall. He hides behind the front door to surprise Laura. The amount of time elapsed from Rob exiting the front door to reappearing from the back hall is approximately 8 seconds. When Laura is shocked to see Rob behind the front door, she asks, "How did you do that so fast?" Rob answers, "I climbed in the bathroom window." Obviously, 8 seconds is not enough time for Rob to have gone all the way around the "outside of the house" and climbed in through a bathroom window. However, 8 seconds was plenty of time for the actor, Dick Van Dyke, to have gone around the "fake studio set" to reenter the scene from the opposite side.
While Sally is on the phone telling everyone about Leo Fassbinder, the shadow of the boom microphone can be seen in the upper right corner of the screen.