diff --git a/transfer_queue/interface.py b/transfer_queue/interface.py
index 0bfc5916..97f25758 100644
--- a/transfer_queue/interface.py
+++ b/transfer_queue/interface.py
@@ -39,6 +39,7 @@
 
 _TRANSFER_QUEUE_CLIENT: Any = None
 _TRANSFER_QUEUE_STORAGE: Any = None
+_TRANSFER_QUEUE_CONTROLLER: Any = None
 
 
 def _maybe_create_transferqueue_client(
@@ -101,9 +102,11 @@ def _init_from_existing() -> bool:
     Returns:
         True if successfully initialized from existing controller, False otherwise.
     """
-
+    global _TRANSFER_QUEUE_CONTROLLER
     try:
-        controller = ray.get_actor("TransferQueueController")
+        if _TRANSFER_QUEUE_CONTROLLER is None:
+            _TRANSFER_QUEUE_CONTROLLER = ray.get_actor("TransferQueueController")
+
     except ValueError:
         logger.info("Called _init_from_existing() but TransferQueueController has not been initialized yet.")
         return False
@@ -112,7 +115,7 @@ def _init_from_existing() -> bool:
 
     conf = None
     while conf is None:
-        conf = ray.get(controller.get_config.remote())
+        conf = ray.get(_TRANSFER_QUEUE_CONTROLLER.get_config.remote())
         if conf is not None:
             _maybe_create_transferqueue_client(conf)
             logger.info("TransferQueueClient initialized.")
@@ -188,7 +191,8 @@ def init(conf: Optional[DictConfig] = None) -> None:
 
     try:
         # Ray will make sure actor with same name can only be created once
-        controller = TransferQueueController.options(name="TransferQueueController", lifetime="detached").remote(  # type: ignore[attr-defined]
+        global _TRANSFER_QUEUE_CONTROLLER
+        _TRANSFER_QUEUE_CONTROLLER = TransferQueueController.options(name="TransferQueueController").remote(  # type: ignore[attr-defined]
             sampler=sampler, polling_mode=final_conf.controller.polling_mode
         )
         logger.info("TransferQueueController has been created.")
@@ -197,14 +201,14 @@ def init(conf: Optional[DictConfig] = None) -> None:
         _init_from_existing()
         return
 
-    controller_zmq_info = process_zmq_server_info(controller)
+    controller_zmq_info = process_zmq_server_info(_TRANSFER_QUEUE_CONTROLLER)
     final_conf.controller.zmq_info = controller_zmq_info
 
     # create distributed storage backends
     final_conf = _maybe_create_transferqueue_storage(final_conf)
 
     # store the config into controller
-    ray.get(controller.store_config.remote(final_conf))
+    ray.get(_TRANSFER_QUEUE_CONTROLLER.store_config.remote(final_conf))
     logger.info(f"TransferQueue config: {final_conf}")
 
     # create client
@@ -224,6 +228,7 @@ def close():
     """
     global _TRANSFER_QUEUE_CLIENT
     global _TRANSFER_QUEUE_STORAGE
+    global _TRANSFER_QUEUE_CONTROLLER
     if _TRANSFER_QUEUE_CLIENT:
         _TRANSFER_QUEUE_CLIENT.close()
         _TRANSFER_QUEUE_CLIENT = None
@@ -237,6 +242,13 @@ def close():
     except Exception:
         pass
 
+    if _TRANSFER_QUEUE_CONTROLLER:
+        try:
+            ray.kill(_TRANSFER_QUEUE_CONTROLLER)
+        except Exception:
+            pass
+        _TRANSFER_QUEUE_CONTROLLER = None
+
     try:
         controller = ray.get_actor("TransferQueueController")
         ray.kill(controller)