diff --git a/Lib/pydoc.py b/Lib/pydoc.py
index a586d35866b038f..e1efe8fc0a1b631 100644
--- a/Lib/pydoc.py
+++ b/Lib/pydoc.py
@@ -2028,12 +2028,12 @@ class Helper:
 
     topics = {
         'TYPES': ('types', 'STRINGS UNICODE NUMBERS SEQUENCES MAPPINGS '
-                  'FUNCTIONS CLASSES MODULES FILES inspect'),
+                  'FUNCTIONS CLASSES MODULES inspect'),
         'STRINGS': ('strings', 'str UNICODE SEQUENCES STRINGMETHODS '
                     'FORMATTING TYPES'),
         'STRINGMETHODS': ('string-methods', 'STRINGS FORMATTING'),
         'FORMATTING': ('formatstrings', 'OPERATORS'),
-        'UNICODE': ('strings', 'encodings unicode SEQUENCES STRINGMETHODS '
+        'UNICODE': ('strings', 'encodings SEQUENCES STRINGMETHODS '
                     'FORMATTING TYPES'),
         'NUMBERS': ('numbers', 'INTEGER FLOAT COMPLEX TYPES'),
         'INTEGER': ('integers', 'int range'),
diff --git a/Lib/test/test_pydoc/test_pydoc.py b/Lib/test/test_pydoc/test_pydoc.py
index a63530c29058275..552b0c7d0759498 100644
--- a/Lib/test/test_pydoc/test_pydoc.py
+++ b/Lib/test/test_pydoc/test_pydoc.py
@@ -2294,6 +2294,19 @@ def test_keywords(self):
         self.assertEqual(sorted(pydoc.Helper.keywords),
                          sorted(keyword.kwlist + ['case', 'match', 'lazy']))
 
+    def test_related_topics(self):
+        # Every related help topic and alias must be something help() can
+        # document.
+        for name, target in (*pydoc.Helper.topics.items(),
+                             *pydoc.Helper.keywords.items()):
+            if isinstance(target, str):
+                target = ('', target)
+            for xref in target[1].split():
+                with self.subTest(topic=name, xref=xref):
+                    buf = StringIO()
+                    pydoc.Helper(output=buf).help(xref)
+                    self.assertNotIn('No help entry found', buf.getvalue())
+
     def test_symbols(self):
         # gh-161414
         for symbol in pydoc.Helper.symbols:
diff --git a/Misc/NEWS.d/next/Library/2026-11-05-12-00-24.gh-issue-161415.NJhrAR.rst b/Misc/NEWS.d/next/Library/2026-11-05-12-00-24.gh-issue-161415.NJhrAR.rst
new file mode 100644
index 000000000000000..22cc4665c253dde
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-11-05-12-00-24.gh-issue-161415.NJhrAR.rst
@@ -0,0 +1,3 @@
+Remove ``FILES`` and ``unicode`` from the related help topics listed by
+:func:`help` for the ``TYPES`` and ``UNICODE`` topics. Neither exists in
+Python 3, so asking for help on them failed.