diff --git a/mmdet/core/evaluation/eval_hooks.py b/mmdet/core/evaluation/eval_hooks.py
index a83b80dbfe7081fa6dbfc13f818339c565076000..bec25eff6d72bed0d1457c5458c31aa101d54f4e 100644
--- a/mmdet/core/evaluation/eval_hooks.py
+++ b/mmdet/core/evaluation/eval_hooks.py
@@ -55,6 +55,10 @@ class DistEvalHook(Hook):
                 shutil.rmtree(self.lock_dir)
             mmcv.mkdir_or_exist(self.lock_dir)
 
+    def after_run(self, runner):
+        if runner.rank == 0:
+            shutil.rmtree(self.lock_dir)
+
     def after_train_epoch(self, runner):
         if not self.every_n_epochs(runner, self.interval):
             return
diff --git a/mmdet/models/__init__.py b/mmdet/models/__init__.py
index aca6399e45e3e21c40d8e2470b233ac0d992888e..8232fda616c11deefd20ba34a12a0679db7b3e4d 100644
--- a/mmdet/models/__init__.py
+++ b/mmdet/models/__init__.py
@@ -1,9 +1,11 @@
-from .detectors import BaseDetector, RPN, FasterRCNN, MaskRCNN
+from .detectors import (BaseDetector, TwoStageDetector, RPN, FastRCNN,
+                        FasterRCNN, MaskRCNN)
 from .builder import (build_neck, build_rpn_head, build_roi_extractor,
                       build_bbox_head, build_mask_head, build_detector)
 
 __all__ = [
-    'BaseDetector', 'RPN', 'FasterRCNN', 'MaskRCNN', 'build_backbone',
-    'build_neck', 'build_rpn_head', 'build_roi_extractor', 'build_bbox_head',
-    'build_mask_head', 'build_detector'
+    'BaseDetector', 'TwoStageDetector', 'RPN', 'FastRCNN', 'FasterRCNN',
+    'MaskRCNN', 'build_backbone', 'build_neck', 'build_rpn_head',
+    'build_roi_extractor', 'build_bbox_head', 'build_mask_head',
+    'build_detector'
 ]
diff --git a/mmdet/models/detectors/__init__.py b/mmdet/models/detectors/__init__.py
index c911d1723d161ae18e78198a53d47921d7937012..a784d5f345605d08df19f258e541f99dc1a794e4 100644
--- a/mmdet/models/detectors/__init__.py
+++ b/mmdet/models/detectors/__init__.py
@@ -1,7 +1,11 @@
 from .base import BaseDetector
+from .two_stage import TwoStageDetector
 from .rpn import RPN
 from .fast_rcnn import FastRCNN
 from .faster_rcnn import FasterRCNN
 from .mask_rcnn import MaskRCNN
 
-__all__ = ['BaseDetector', 'RPN', 'FastRCNN', 'FasterRCNN', 'MaskRCNN']
+__all__ = [
+    'BaseDetector', 'TwoStageDetector', 'RPN', 'FastRCNN', 'FasterRCNN',
+    'MaskRCNN'
+]