diff --git a/photoswipe.theme.inc b/photoswipe.theme.inc
index 2082f63..9fa02f9 100644
--- a/photoswipe.theme.inc
+++ b/photoswipe.theme.inc
@@ -7,6 +7,7 @@
 
 use Drupal\Core\Language\Language;
 use Drupal\image\Entity\ImageStyle;
+use Drupal\media\MediaInterface;
 
 /**
  * Prepares variables for a Photoswipe image field formatter.
@@ -18,11 +19,13 @@ use Drupal\image\Entity\ImageStyle;
  *
  * @ingroup themeable
  */
-function template_preprocess_photoswipe_image_formatter(array &$variables)
-{
+function template_preprocess_photoswipe_image_formatter(array &$variables) {
   $item = $variables['item'];
   $settings = $variables['display_settings'];
-  $entity = $item->getParent()->getParent()->getValue();
+  if ($item->entity instanceof MediaInterface && $item->entity->hasField($settings['photoswipe_reference_image_field'])) {
+    $item = $item->entity->get($settings['photoswipe_reference_image_field']);
+  }
+  $entity = $item->getParent()->getValue();
   $uri = $item->entity->getFileUri();
   $alt = !empty($item->alt) ? $item->alt : '';
   $title = !empty($item->title) ? $item->title : '';
@@ -51,8 +54,9 @@ function template_preprocess_photoswipe_image_formatter(array &$variables)
   if ($image_file->isValid()) {
     $image_width = $image_file->getWidth();
     $image_height = $image_file->getHeight();
-  } else {
-    $image_width = $image_height = null;
+  }
+  else {
+    $image_width = $image_height = NULL;
   }
 
   $dimensions = [];
@@ -71,7 +75,8 @@ function template_preprocess_photoswipe_image_formatter(array &$variables)
 
     // Set the dimensions.
     $style->transformDimensions($dimensions, $uri);
-  } else {
+  }
+  else {
     $path = file_create_url($uri);
   }
 
@@ -95,22 +100,23 @@ function template_preprocess_photoswipe_image_formatter(array &$variables)
       case 'node_title':
         if (!empty($entity->title)) {
           $caption = $entity->title->value;
-        } else {
+        }
+        else {
           $caption = $alt;
         }
         break;
 
       default:
-        // Assume the user wants to use another node field as the caption
+        // Assume the user wants to use another node field as the caption.
         $field_view['#view_mode'] = ($settings['photoswipe_view_mode']) ? $settings['photoswipe_view_mode'] : 'default';
         if (!isset($entity->{$caption_setting})) {
           // No such field exists. We'd better warn and use something reliable.
           $id = $entity->id();
           $msg = "'Photoswipe Caption' is unset for field view '@fv' on node: @nid.";
-          \Drupal::logger('photoswipe')->warning($msg, array(
+          \Drupal::logger('photoswipe')->warning($msg, [
             '@fv' => $field_view['#view_mode'],
-            '@nid' => $id
-          ));
+            '@nid' => $id,
+          ]);
           // Fallback to alt text:
           $caption = $alt;
           break;
@@ -119,7 +125,8 @@ function template_preprocess_photoswipe_image_formatter(array &$variables)
         $caption = render($field_view);
         break;
     }
-  } else {
+  }
+  else {
     $caption = $alt;
   }
 
@@ -128,7 +135,7 @@ function template_preprocess_photoswipe_image_formatter(array &$variables)
   $variables['attributes']['class'][] = 'photoswipe';
   $variables['attributes']['data-size'] = $dimensions['width'] . 'x' . $dimensions['height'];
   $variables['attributes']['data-overlay-title'] = $caption;
-  if($image['#style_name'] === 'hide'){
+  if ($image['#style_name'] === 'hide') {
     // Do not display if hidden is selected:
     $variables['attributes']['class'][] = 'hidden';
   }
diff --git a/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php b/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php
index a99aea7..8396d5f 100644
--- a/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php
+++ b/src/Plugin/Field/FieldFormatter/PhotoswipeFieldFormatter.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\photoswipe\Plugin\Field\FieldFormatter;
 
+use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\Field\FieldItemListInterface;
 use Drupal\Core\Field\FormatterBase;
 use Drupal\Core\Form\FormStateInterface;
@@ -14,6 +15,7 @@ use Drupal\image\Entity\ImageStyle;
  *   id = "photoswipe_field_formatter",
  *   label = @Translation("Photoswipe"),
  *   field_types = {
+ *     "entity_reference",
  *     "image"
  *   }
  * )
@@ -28,6 +30,7 @@ class PhotoswipeFieldFormatter extends FormatterBase {
       'photoswipe_node_style_first' => '',
       'photoswipe_node_style' => '',
       'photoswipe_image_style' => '',
+      'photoswipe_reference_image_field' => '',
       'photoswipe_caption' => '',
       'photoswipe_view_mode' => '',
     ] + parent::defaultSettings();
@@ -71,11 +74,14 @@ class PhotoswipeFieldFormatter extends FormatterBase {
       'alt' => $this->t('Image alt tag'),
       'node_title' => $this->t('Entity title'),
     ];
-    // Add the other node fields as options.
-    if (!empty($form['#fields'])) {
-      foreach ($form['#fields'] as $node_field) {
-        if ($node_field != $this->fieldDefinition->getName()) {
-          $caption_options[$node_field] = $node_field;
+
+    $element = $this->addEntityReferenceSettings($element);
+
+    // Add the other parent entity fields as options.
+    if (isset($form['#fields'])) {
+      foreach ($form['#fields'] as $parent_field) {
+        if ($parent_field != $this->fieldDefinition->getName()) {
+          $caption_options[$parent_field] = $parent_field;
         }
       }
     }
@@ -98,6 +104,49 @@ class PhotoswipeFieldFormatter extends FormatterBase {
   }
 
   /**
+   * Adds extra settings related when dealing with an entity reference.
+   *
+   * @param array $element
+   *   The settings form structure of this formatter.
+   *
+   * @return array
+   *   The modified settings form structure of this formatter.
+   */
+  private function addEntityReferenceSettings(array $element) {
+    if ($this->fieldDefinition->getType() !== 'entity_reference') {
+      return $element;
+    }
+
+    $target_type = $this->fieldDefinition->getSetting('target_type');
+    $target_bundles = $this->fieldDefinition->getSetting('handler_settings')['target_bundles'];
+
+    /* @var $fields FieldDefinitionInterface[] */
+    $fields = [];
+    foreach ($target_bundles as $bundle) {
+      $fields += \Drupal::service('entity_field.manager')
+        ->getFieldDefinitions($target_type, $bundle);
+    }
+    $fields = array_filter($fields, function (FieldDefinitionInterface $field) {
+      return $field->getType() === 'image' && $field->getName() !== 'thumbnail';
+    });
+
+    $field_options = [];
+    foreach ($fields as $name => $field) {
+      $field_options[$name] = $field->getName();
+    }
+
+    $element['photoswipe_reference_image_field'] = [
+      '#title' => $this->t('Image field of the referenced entity'),
+      '#type' => 'select',
+      '#default_value' => $this->getSetting('photoswipe_reference_image_field'),
+      '#options' => $field_options,
+      '#description' => $this->t('Field that contains the image to be used.'),
+    ];
+
+    return $element;
+  }
+
+  /**
    * {@inheritdoc}
    */
   public function settingsSummary() {
@@ -135,6 +184,10 @@ class PhotoswipeFieldFormatter extends FormatterBase {
       $summary[] = $this->t('photoswipe image style: Original image');
     }
 
+    if ($this->getSetting('photoswipe_reference_image_field')) {
+      $summary[] = $this->t('Referenced entity image field: @field', ['@field' => $this->getSetting('photoswipe_reference_image_field')]);
+    }
+
     if ($this->getSetting('photoswipe_caption')) {
       $caption_options = [
         'alt' => $this->t('Image alt tag'),
@@ -162,6 +215,8 @@ class PhotoswipeFieldFormatter extends FormatterBase {
 
     if (!empty($items)) {
       \Drupal::service('photoswipe.assets_manager')->attach($elements);
+      $elements['#prefix'] = '<div class="photoswipe-gallery">';
+      $elements['#suffix'] = '</div>';
     }
 
     foreach ($items as $delta => $item) {