The Recycled Citizen

A member of the Senior Citizens' Recycling Center has turned up dead in a part of Boston where he would never have been found alive. Why did he go there? How did he get there? Why was he killed? And what are the mysterious purple soda cans all about? And Tigger? What is she doing hanging around?
Sarah and Max Bittersohn want to discover the answers to these questions before Dolph and Mary Kelling's charitable work is sabotaged and the SCRC given a bad name.