diff --git a/guides/source/action_controller_overview.md b/guides/source/action_controller_overview.md
index 8dfecd0190..cd4a1a0792 100644
--- a/guides/source/action_controller_overview.md
+++ b/guides/source/action_controller_overview.md
@@ -209,7 +209,7 @@ class PeopleController < ActionController::Base
   # Request reply.
   def update
     person = current_account.people.find(params[:id])
-    person.update_attributes!(person_params)
+    person.update!(person_params)
     redirect_to person
   end