In staking out a liquor store to be robbed, Holmes expresses boredom , and asks Yoyo about it. Yoyo replies "I'm Not programmed for boredom. During times of inactivity such as this long waiting period, my mind is simply a blank." They chase a dog who snatches purses from lady-pedestrians and lose the dog at a fence. At headquarters, it's found to be second such theft.
Next time, a Police-Woman Maxine acts as a decoy with purse, with Holmes and Yoyo staking her out. And this is the second time that Yoyo's Robot-Ears hears an unusual Whistling sound which Holmes canNot hear. When the dog snatches purse, Maxine does not let go so she's pulled along and then dragged along when she lands on a Skateboard. Finally when she lets go of the leash,she winds up in car-wash. The dog leaves the stolen purse with a Councilman, so Holmes and Yoyo mistakenly apprehend him, much to Holmes' embarrassment.
At police headquarters,Yoyo mentions the Whistle he heard twice, so both he and Holmes hit on the idea of Ultra-Sonic whistle-Commands. With that in mind,they visit lady at an Animal-training school, and she verifies about the whistle and that to be effective it must be used within the radius of two city blocks.
Yoyo produces robot-Photos of the two robbery scenes, triggered by Pressing His Nose, and each photo Slides Out Of His Mouth. At first,he has problems with his nose so he sprays graphite powder into his nostril for remedy. Three suspects common to Both photographs are a vendor, a flutist, and a hotel doorman. To Holmes and Yoyo, it's obviously the flutist, but when they question him, he comes out clean. Suddenly, another dog snatching takes place, and they finally apprehend the doorman as the culprit.moreless