I'll throw in some more to the story.
Just as the two men were about to confront Mr. Williams, and ice cream truck starts driving down the road. The two men, upon seeing the truck, get back in their car and drive quickly away. Mr. Williams grabs John and pulls him into his car quickly, saying "Get in and strap in! This is going to be fast!" He starts going in reverse as fast as possible while maintaining control of the vehicle. John noticed the ice cream truck started sppeding up, too.