Heo Sung-tae (Korean: 허성태, Korean pronunciation: [hʌ sʌŋ tɛ], born October 20, 1977)[1] is a South Korean actor with over sixty film and television credits. He gained national prominence in the 2016 period thriller film The Age of Shadows and became recognized by international audiences for his portrayal of Jang Deok-su in the hit series Squid Game.