RESEARCH and DESTROY

You need to complete a mission with the "Uncertainty Helmet" not only equipped to one of your scientists but also in use when you finish the misson. (Looks like 4 scientists ta-da!) Just make sure that scientists have the last turn or else you risk the supernaturals hitting your scientists before the official mission complete. (Getting hit despawns the fake scientist)

You get all your gadgets from researching them at a university on the world map using $cience. The order that they become available to you is random each playthough. So you may need to play awhile until you have access to it or simply make a new campaign if your looking just for this.