Luthor the Doberman, a former attack dog, has a good home with Savannah Drysdale, but every time a certain truck passes he goes into a frenzy, while Griffin Bing is caught up in trying to beat his rival, Darren Vader, at an invention contest. Luthor, a former attack dog, is trying to be on his best behavior now that he's in the care of Savannah, a girl who's easily a dog's best friend. But every time a certain truck passes by her house, Luthor goes into attack mode and chaos ensues. Book #7