diff --git a/Lib/test/test_importlib/extension/test_loader.py b/Lib/test/test_importlib/extension/test_loader.py
index 66ac2b1..5813ade 100644
--- a/Lib/test/test_importlib/extension/test_loader.py
+++ b/Lib/test/test_importlib/extension/test_loader.py
@@ -170,6 +170,13 @@ class MultiPhaseExtensionModuleTests(abc.LoaderTests):
         loader.exec_module(module)
         return module
 
+    def test_load_submodule(self):
+        '''Test loading a simulated submodule'''
+        module = self.load_module_by_name('pkg.' + self.name)
+        self.assertIsInstance(module, types.ModuleType)
+        self.assertEqual(module.__name__, 'pkg.' + self.name)
+        self.assertEqual(module.str_const, 'something different')
+
     def test_load_twice(self):
         '''Test that 2 loads result in 2 module objects'''
         module1 = self.load_module_by_name(self.name)
diff --git a/Python/importdl.c b/Python/importdl.c
index bb90391..579d2c5 100644
--- a/Python/importdl.c
+++ b/Python/importdl.c
@@ -45,7 +45,7 @@ get_encoded_name(PyObject *name, const char **hook_prefix) {
     if (lastdot < -1) {
         return NULL;
     } else if (lastdot >= 0) {
-        tmp = PyUnicode_Substring(name, lastdot, name_len);
+        tmp = PyUnicode_Substring(name, lastdot + 1, name_len);
         if (tmp == NULL)
             return NULL;
         name = tmp;