diff --git a/gallery_dl/extractor/bellazon.py b/gallery_dl/extractor/bellazon.py
index ce50a918..0d3e615f 100644
--- a/gallery_dl/extractor/bellazon.py
+++ b/gallery_dl/extractor/bellazon.py
@@ -130,7 +130,7 @@ class BellazonExtractor(Extractor):
         author = schema["author"]
         stats = schema["interactionStatistic"]
         url_t = schema["url"]
-        url_a = author["url"]
+        url_a = author.get("url") or ""
 
         path = text.split_html(text.extr(
             page, '<nav class="ipsBreadcrumb', "</nav>"))[2:-1]
@@ -151,8 +151,12 @@ class BellazonExtractor(Extractor):
 
         thread["id"], _, thread["slug"] = \
             url_t.rsplit("/", 2)[1].partition("-")
-        thread["author_id"], _, thread["author_slug"] = \
-            url_a.rsplit("/", 2)[1].partition("-")
+
+        if url_a:
+            thread["author_id"], _, thread["author_slug"] = \
+                url_a.rsplit("/", 2)[1].partition("-")
+        else:
+            thread["author_id"] = thread["author_slug"] = ""
 
         return thread
 
@@ -169,8 +173,11 @@ class BellazonExtractor(Extractor):
         if (pos := post["content"].find(">")) >= 0:
             post["content"] = post["content"][pos+1:].strip()
 
-        post["author_id"], _, post["author_slug"] = \
-            post["author_url"].rsplit("/", 2)[1].partition("-")
+        if url_a := post["author_url"]:
+            post["author_id"], _, post["author_slug"] = \
+                url_a.rsplit("/", 2)[1].partition("-")
+        else:
+            post["author_id"] = post["author_slug"] = ""
 
         return post
 
diff --git a/gallery_dl/version.py b/gallery_dl/version.py
index bc70f747..459eab97 100644
--- a/gallery_dl/version.py
+++ b/gallery_dl/version.py
@@ -6,5 +6,5 @@
 # it under the terms of the GNU General Public License version 2 as
 # published by the Free Software Foundation.
 
-__version__ = "1.30.10"
+__version__ = "1.31.0-dev"
 __variant__ = None
diff --git a/test/results/bellazon.py b/test/results/bellazon.py
index dfdb5679..d1e60cd9 100644
--- a/test/results/bellazon.py
+++ b/test/results/bellazon.py
@@ -307,6 +307,49 @@ __tests__ = (
     },
 },
 
+{
+    "#url"     : "https://www.bellazon.com/main/topic/56-candids/",
+    "#comment" : "'Guest' author (#8397)",
+    "#class"   : bellazon.BellazonThreadExtractor,
+    "#options" : {"order-posts": "asc"},
+    "#range"   : "1",
+    "#results" : (
+        "https://www.bellazon.com/main/uploads/monthly_11_2004/post-0-0-1593851439-26962.jpg",
+    ),
+
+    "post"     : {
+        "author_id"  : "",
+        "author_slug": "",
+        "author_url" : "",
+        "content"    : """<a href="https://www.bellazon.com/main/uploads/monthly_11_2004/post-0-0-1593851439-26962.jpg" class="ipsAttachLink ipsAttachLink_image"><img data-fileid="292" src="https://www.bellazon.com/main/uploads/monthly_11_2004/post-0-0-1593851439-26962_thumb.jpg" class="ipsImage ipsImage_thumbnailed" alt="sss.jpg" loading="lazy"></a>""",
+        "count"      : 1,
+        "date"       : "dt:2004-11-21 03:09:51",
+        "id"         : "292",
+    },
+    "thread"   : {
+        "author"      : "Guest",
+        "author_id"   : "",
+        "author_slug" : "",
+        "author_url"  : "",
+        "date"        : "dt:2004-11-21 01:44:59",
+        "date_updated": "type:datetime",
+        "description" : "Welcome to the Alessandra Ambrosio Candids gallery.  Please only post candid, unposed, off-guard, or funny images in this thread.",
+        "id"          : "56",
+        "posts"       : range(13_000, 30_000),
+        "section"     : "Alessandra Ambrosio",
+        "slug"        : "candids",
+        "title"       : "Candids",
+        "url"         : "https://www.bellazon.com/main/topic/56-candids/",
+        "views"       : range(8_000_000, 10_000_000),
+        "path"        : [
+            "Females",
+            "Female Fashion Models",
+            "Alessandra Ambrosio",
+            "Candids",
+        ],
+    },
+},
+
 {
     "#url"     : "https://www.bellazon.com/main/forum/3-actresses/",
     "#class"   : bellazon.BellazonForumExtractor,