This plan is for the Ghost Sniffer that Dr. Venkman used in the scene where he analyzed Dana's apartment. The plan is very simple to follow. It lists the necessary materials, step by step instructions, and a diagram of where all the pieces go. Soon, you too will be sniffing out ghosts around your own house or apartment. It's just a shame that we never really did learn what this toy's real function was. At least we get a quote with it: "It's techinical, it's one of our little toys."