diff --git a/src/NzbDrone.Core/MetadataSource/BookInfo/BookInfoProxy.cs b/src/NzbDrone.Core/MetadataSource/BookInfo/BookInfoProxy.cs
index adebe9ca9..c77aec858 100644
--- a/src/NzbDrone.Core/MetadataSource/BookInfo/BookInfoProxy.cs
+++ b/src/NzbDrone.Core/MetadataSource/BookInfo/BookInfoProxy.cs
@@ -507,12 +507,16 @@ private List<Book> MapSearchResult(List<int> ids)
 
         private List<Book> MapBulkBook(BulkBookResource resource)
         {
-            var authors = resource.Authors.Select(MapAuthorMetadata).ToDictionary(x => x.ForeignAuthorId, x => x);
-
-            var series = resource.Series.Select(MapSeries).ToList();
-
             var books = new List<Book>();
 
+            if (resource == null)
+            {
+                return books;
+            }
+
+            var authors = resource.Authors.Select(MapAuthorMetadata).ToDictionary(x => x.ForeignAuthorId, x => x);
+            var series = resource.Series.Select(MapSeries).ToList();
+
             foreach (var work in resource.Works)
             {
                 var book = MapBook(work);