In the 17th century, when stone walls were a prominent feature of castles across Japan, the town of Sakamoto in Japan's Shiga Prefecture became famous for its stonemasons' expert technique. But when feudalism ended 150 years ago, many castles were destroyed - though many stonemasons continued to pass down their craft. SAMURAI WALL follows a 15th-generation Japanese master stonemason, Suminori Awata, as he revives his family's ancient techniques to complete a modern-day commission: a castle-style wall in a new, modern office tower in downtown Dallas, Texas.