diff --git a/picard/script.py b/picard/script.py
index 7acd6361b..822a8f9aa 100644
--- a/picard/script.py
+++ b/picard/script.py
@@ -863,9 +863,12 @@ def func_firstwords(parser, text, length):
     if len(text) <= length:
         return text
     else:
-        if text[length] == ' ':
-            return text[:length]
-        return text[:length].rsplit(' ', 1)[0]
+        try:
+            if text[length] == ' ':
+                return text[:length]
+            return text[:length].rsplit(' ', 1)[0]
+        except IndexError:
+            return ''
 
 
 @script_function()
diff --git a/test/test_script.py b/test/test_script.py
index b6e329801..af5cb2cfc 100644
--- a/test/test_script.py
+++ b/test/test_script.py
@@ -456,6 +456,8 @@ class ScriptParserTest(PicardTestCase):
         self.assertScriptResultEquals("$firstwords(Abc Def Ghi,0)", "")
         self.assertScriptResultEquals("$firstwords(Abc Def Ghi,NaN)", "")
         self.assertScriptResultEquals("$firstwords(Abc Def Ghi,)", "")
+        self.assertScriptResultEquals("$firstwords(Abc Def Ghi,-2)", "Abc Def")
+        self.assertScriptResultEquals("$firstwords(Abc Def Ghi,-50)", "")
 
     def test_cmd_startswith(self):
         self.assertScriptResultEquals("$startswith(abc,a)", "1")