Amazon.com has Batman: Under the Red Hood (Blu-Ray) on sale for $9.19. Shipping is free with Prime or if you spend $35 or more.

Note, item is temporarily out of stock; order now and Amazon will deliver when available.

Alternatively, for Target REDcard holders:

Target.com also has Batman: Under the Red Hood (Blu-ray) on sale for $5. Free shipping with your REDcard and save an additional 5%.