diff --git a/lib/charty/table_adapters/pandas_adapter.rb b/lib/charty/table_adapters/pandas_adapter.rb
index 9aea54ee..1fec9c31 100644
--- a/lib/charty/table_adapters/pandas_adapter.rb
+++ b/lib/charty/table_adapters/pandas_adapter.rb
@@ -208,7 +208,7 @@ def [](key)
                 when PyCall::Tuple
                   key
                 else
-                  PyCall::Tuple.new(*key.to_a)
+                  PyCall::Tuple.new(*Array(key))
                 end
           Charty::Table.new(@groupby.get_group(key))
         end