diff --git a/nselib/stdnse.lua b/nselib/stdnse.lua
index 2d60c3268..0f75a7c5d 100644
--- a/nselib/stdnse.lua
+++ b/nselib/stdnse.lua
@@ -834,14 +834,11 @@ end
 local function arg_value(argname)
   if nmap.registry.args[argname] then
     return nmap.registry.args[argname]
-  else
-    -- if scriptname.arg is not there, check "arg"
-    local argument_frags = strsplit("%.", argname)
-    if #argument_frags > 0 then
-      if nmap.registry.args[argument_frags[2]] then
-        return nmap.registry.args[argument_frags[2]]
-      end
-    end
+  end
+  -- if scriptname.arg is not there, check "arg"
+  local argument_frags = strsplit("%.", argname)
+  if nmap.registry.args[argument_frags[2]] then
+    return nmap.registry.args[argument_frags[2]]
   end
 
   for _, v in ipairs(nmap.registry.args) do
@@ -849,6 +846,7 @@ local function arg_value(argname)
       return 1
     end
   end
+  return nil
 end
 
 --- Parses the script arguments passed to the --script-args option.