diff --git a/demos/web/server.py b/demos/web/server.py
index f7c4ea8..8d2d5d4 100755
--- a/demos/web/server.py
+++ b/demos/web/server.py
@@ -355,6 +355,7 @@ class OpenFaceServerProtocol(WebSocketServerProtocol):
                 "type": "ANNOTATED",
                 "content": content
             }
+            plt.close()
             self.sendMessage(json.dumps(msg))
 
 if __name__ == '__main__':