diff --git a/mockredis/script.py b/mockredis/script.py
index c0a3d48..afc41cf 100644
--- a/mockredis/script.py
+++ b/mockredis/script.py
@@ -24,7 +24,7 @@ def __call__(self, keys=[], args=[], client=None):
             if not client.script_exists(self.sha)[0]:
                 self.sha = client.script_load(self.script)
 
-            return self._execute_lua(keys, args, client)
+            return self._execute_lua([str(key) for key in keys], [str(arg) for arg in args], client)
 
     def _execute_lua(self, keys, args, client):
         """