diff --git a/project/Terkoiz.MapZoneHighlighter/BoundedBoxes/ColliderBoundsController.cs b/project/Terkoiz.MapZoneHighlighter/BoundedBoxes/ColliderBoundsController.cs
index 20de414..fc9fbf2 100644
--- a/project/Terkoiz.MapZoneHighlighter/BoundedBoxes/ColliderBoundsController.cs
+++ b/project/Terkoiz.MapZoneHighlighter/BoundedBoxes/ColliderBoundsController.cs
@@ -52,6 +52,11 @@ namespace Terkoiz.MapZoneHighlighter.BoundedBoxes
 
         private void OnGUI()
         {
+            if (Camera.main == null)
+            {
+                return;
+            }
+
             ScreenPosition = UIDrawingUtil.WorldPointToScreenPoint(transform.position);
             IsOnScreen = UIDrawingUtil.IsScreenPointVisible(ScreenPosition);
             DistanceToCamera = Vector3.Distance(Camera.main.transform.position, transform.position);