We have extended our investigation of sunspot regions, with particular attention to the physics of the transition region between the chromosphere and the corona. In sunspot plumes, the most prominent features in the transition region intensity maps, we find downflows exceeding 25 km s−1. The observations show that the flow cannot be maintained by inflow from the corona and prompt a search for the origin of the flow and its possible relation to the origin of the sunspot plume. We find that the downflows in sunspot plumes are maintained by gas at transition region temperatures, streaming in flow channels from locations well outside the sunspot. Hence, the flow pattern in the transition region shows similarities to the inverse Evershed flow in the chromosphere. We present a working hypothesis that is based on the siphon flow mechanism.