William Jannert is a Swedish actor based in Skåne in southern Sweden. He plays Jon in the Netflix limited series Land of Sin (Synden, 2026), created and directed by Peter Grönlund, which was nominated for best TV drama at the Kristallen awards. His earlier work includes young Mattias in the Viaplay mini-series End of Summer (2023), Elias in the feature film Scapegoat (2024), and Max in SVT's Festen (2021). He grew up bilingual and performs at native level in Swedish and German, alongside fluent English. He is represented by Hammarström Agency in Stockholm.