diff --git a/fieldblock.module b/fieldblock.module
index 7835d98155bd8bc65fbfba65620de131a22f4d39..0f0a4b55035375f88b1e45399be379474075e4e6 100644
--- a/fieldblock.module
+++ b/fieldblock.module
@@ -161,6 +161,11 @@ function fieldblock_block_view($delta = '') {
  * array.
  */
 function fieldblock_field_attach_view_alter(&$output, $context) {
+  // Do nothing if essential information is missing.
+  if (!isset($output['#bundle'], $context['entity_type'], $context['view_mode'])) {
+    return;
+  }
+
   $entity_type = $context['entity_type'];
   $bundle = $output['#bundle'];
   $view_mode = $context['view_mode'];