diff --git a/adv_control/nodes_main.py b/adv_control/nodes_main.py
index a5bc2aa..e8aaee0 100644
--- a/adv_control/nodes_main.py
+++ b/adv_control/nodes_main.py
@@ -114,7 +114,7 @@ class AdvancedControlNetApply(io.ComfyNode):
                          mask_optional: Tensor=None, vae_optional=None,
                          timestep_kf: TimestepKeyframeGroup=None, latent_kf_override: LatentKeyframeGroup=None,
                          weights_override: ControlWeights=None, control_apply_to_uncond=False, extra_concat=None):
-        if strength == 0:
+        if strength == 0 or (mask_optional is not None and mask_optional.count_nonzero().item() == 0):
             return io.NodeOutput(positive, negative)
         if extra_concat is None:
             extra_concat = []
diff --git a/tests/test_modern_control.py b/tests/test_modern_control.py
index 330f42b..c566f6c 100644
--- a/tests/test_modern_control.py
+++ b/tests/test_modern_control.py
@@ -156,6 +156,26 @@ class T2IAdapterTests(unittest.TestCase):
         self.assertIs(control.cond_hint_original, original_hint)
 
 
+class AdvancedControlNetApplyTests(unittest.TestCase):
+    def test_all_zero_effect_mask_returns_original_conditioning(self):
+        positive = [[sentinel.positive_tensor, {"name": "positive"}]]
+        negative = [[sentinel.negative_tensor, {"name": "negative"}]]
+
+        result = AdvancedControlNetApply.execute(
+            positive=positive,
+            negative=negative,
+            control_net=sentinel.control_net,
+            image=torch.ones((1, 8, 8, 3)),
+            strength=1.0,
+            start_percent=0.0,
+            end_percent=1.0,
+            mask_optional=torch.zeros((1, 8, 8)),
+        )
+
+        self.assertIs(result.args[0], positive)
+        self.assertIs(result.args[1], negative)
+
+
 class AdvancedInpaintingApplyTests(unittest.TestCase):
     def test_source_mask_and_effect_mask_stay_independent(self):
         image = torch.ones((1, 2, 2, 3))