diff --git a/classes/ComicPressNavigation.inc b/classes/ComicPressNavigation.inc
index bcc4a46..938583e 100644
--- a/classes/ComicPressNavigation.inc
+++ b/classes/ComicPressNavigation.inc
@@ -11,7 +11,7 @@ class ComicPressNavigation {
   }
   // @codeCoverageIgnoreEnd
 
-  function get_post_nav($post) {
+  function get_post_nav($post, $restrictions = null) {
     $nav = array();
     if (is_object($post)) {
 	    if (isset($post->ID)) {
@@ -24,14 +24,16 @@ class ComicPressNavigation {
 		    	 return $nav;
 		    }
 
+		    $categories = $this->_storyline->build_from_restrictions($restrictions);
+
 		    // global previous/next
 		    foreach (array('previous', 'next') as $field) {
-		      $nav[$field] = $this->_dbi->{"get_${field}_comic"}(null, $post);
+		      $nav[$field] = $this->_dbi->{"get_${field}_comic"}($categories, $post);
 		    }
 
 		    // global first/last
 		    foreach (array('first', 'last') as $field) {
-		      $nav[$field] = $this->_dbi->{"get_${field}_comic"}(null);
+		      $nav[$field] = $this->_dbi->{"get_${field}_comic"}($categories);
 		    }
 
 		    if ($category = $this->_storyline->get_valid_post_category($post->ID)) {
@@ -68,4 +70,4 @@ class ComicPressNavigation {
   }
 }
 
-?>
\ No newline at end of file
+?>
diff --git a/classes/ComicPressStoryline.inc b/classes/ComicPressStoryline.inc
index b92337a..b9566e0 100644
--- a/classes/ComicPressStoryline.inc
+++ b/classes/ComicPressStoryline.inc
@@ -16,7 +16,10 @@ class ComicPressStoryline {
    */
 	function get_flattened_storyline() {
 		$comicpress = &ComicPress::get_instance();
-	  return $comicpress->comicpress_options['storyline_order'];
+		if (isset($comicpress->comicpress_options['storyline_order'])) {
+			return $comicpress->comicpress_options['storyline_order'];
+		}
+		return false;
 	}
 
   /**
diff --git a/test/ComicPressNavigationTest.php b/test/ComicPressNavigationTest.php
index d55b111..49eb163 100644
--- a/test/ComicPressNavigationTest.php
+++ b/test/ComicPressNavigationTest.php
@@ -35,25 +35,27 @@ class ComicPressNavigationTest extends PHPUnit_Framework_TestCase {
     $dbi = $this->getMock('ComicPressDBInterface', array('get_previous_comic', 'get_next_comic', 'get_first_comic', 'get_last_comic'));
     $storyline = new ComicPressStoryline();
 
-    $storyline->_structure = array(
-      '1' => array('next' => 2),
-      '2' => array('previous' => 1, 'next' => 3),
-      '3' => array('previous' => 2)
-    );
+    $storyline->set_flattened_storyline('0/1,0/1/2,0/3');
 
     wp_insert_post(array('ID' => 1));
     $post = get_post(1);
 
     wp_set_post_categories(1, array(2));
 
-    $dbi->expects($this->at(0))->method('get_previous_comic')->with(null, $post);
-    $dbi->expects($this->at(1))->method('get_next_comic')->with(null, $post);
-    $dbi->expects($this->at(2))->method('get_first_comic')->with(null);
-    $dbi->expects($this->at(3))->method('get_last_comic')->with(null);
+    $dbi->expects($this->at(0))->method('get_previous_comic')->with(array(1,2,3), $post);
+    $dbi->expects($this->at(1))->method('get_next_comic')->with(array(1,2,3), $post);
+    $dbi->expects($this->at(2))->method('get_first_comic')->with(array(1,2,3));
+    $dbi->expects($this->at(3))->method('get_last_comic')->with(array(1,2,3));
     $dbi->expects($this->at(4))->method('get_previous_comic')->with(2, $post);
     $dbi->expects($this->at(5))->method('get_next_comic')->with(2, $post);
-    $dbi->expects($this->at(6))->method('get_first_comic')->with(1)->will($this->returnValue((object)array('ID' => 1)));
-    $dbi->expects($this->at(7))->method('get_first_comic')->with(3)->will($this->returnValue((object)array('ID' => 1)));
+    // level
+    $dbi->expects($this->at(6))->method('get_first_comic')->with(2)->will($this->returnValue((object)array('ID' => 1)));
+    // parent
+    $dbi->expects($this->at(7))->method('get_first_comic')->with(1)->will($this->returnValue((object)array('ID' => 1)));
+    // previous
+    $dbi->expects($this->at(8))->method('get_first_comic')->with(1)->will($this->returnValue((object)array('ID' => 1)));
+    // next
+    $dbi->expects($this->at(9))->method('get_first_comic')->with(3)->will($this->returnValue((object)array('ID' => 1)));
 
     $this->nav->_dbi = $dbi;
     $this->nav->_storyline = $storyline;
@@ -102,4 +104,4 @@ class ComicPressNavigationTest extends PHPUnit_Framework_TestCase {
   }
 }
 
-?>
\ No newline at end of file
+?>
diff --git a/test/ComicPressStorylineTest.php b/test/ComicPressStorylineTest.php
index 555d2ff..01b85da 100644
--- a/test/ComicPressStorylineTest.php
+++ b/test/ComicPressStorylineTest.php
@@ -691,4 +691,4 @@ class ComicPressStorylineTest extends PHPUnit_Framework_TestCase {
   }
 }
 
-?>
\ No newline at end of file
+?>