Stop! Or my Duke will shoot! The Internet of Things needs an application architecture that enables the gathering of information from many devices; aggregation and processing of that data, including human supervision and intervention; and, finally, appropriate reaction to close the cybernetic feedback loop. This session proposes a reactive architecture based on OpenDolphin in which all application logic runs on the Java EE platform. The attendees will become part of a live experiment in which they have to collaborate, with the help of many devices, to balance a JavaFX 3D scene so that a physical shooting device in the room can launch its missiles. Expect a lot of fun and some surprises.